-
a
aindefinite articlenot any particular or certain one of a class or group.
-
A
Anounthe first letter of the English alphabet, a vowel.
-
Å
Åangstrom.
-
a'
a'adjectiveall.
-
a-
a-a reduced form of the Old English preposition on, meaning “on,” “in,” “into,” “to,” “toward,” preserved before a noun in a prepositional phrase, forming a predicate adjective or an adverbial element (afoot; abed; ashore; aside; away ), or before an adjective (afar; aloud; alow ), as a moribund prefix with a verb (acknowledge ), and in archaic and dialectal use before a present participle in -ing (set the bells aringing ); and added to a verb stem with the force of a present participle (ablaze; agape; aglow; astride; and originally,awry ).
-
-a
-aa plural ending of nouns borrowed from Greek and Latin.
-
A-
A-atomic (used in combination).
-
a.
a.abbreviationyear.
-
A.
A.abbreviationyear.
-
a–
a–A prefix meaning “without” or “not” when forming an adjective (such as amorphous, without form, or atypical, not typical), and “absence of” when forming a noun (such as arrhythmia, absence of rhythm). Before a vowel or h it becomes an– (as in anhydrous, anoxia).
a
1 Americanindefinite article
-
not any particular or certain one of a class or group.
a man; a chemical; a house.
-
a certain; a particular.
one at a time; two of a kind; A Miss Johnson called.
-
another; one typically resembling.
a Cicero in eloquence; a Jonah.
-
one (used before plural nouns that are preceded by a quantifier singular in form): a hundred men (comparehundreds of men ); a dozen times (comparedozens of times ).
-
indefinitely or nonspecifically (used with adjectives expressing number).
a great many years; a few stars.
-
one (used before a noun expressing quantity).
a yard of ribbon; a score of times.
-
any; a single.
not a one.
preposition
preposition
auxiliary verb
abbreviation
noun
-
A's,
plural
-
As,
plural
-
a's,
plural
-
as
plural
-
the first letter of the English alphabet, a vowel.
-
any spoken sound represented by the letter A or a, as in bake, hat, father, or small.
-
something having the shape of an A .
-
a written or printed representation of the letter A or a.
-
a device, as a printer's type, for reproducing the letter A or a.
idioms
-
not know from A to B, to know nothing; be ignorant.
-
from A to Z, from beginning to end; thoroughly; completely.
He knows the Bible from A to Z.
-
the first in order or in a series.
-
Sometimes a
-
(in some grading systems) a grade or mark, as in school or college, indicating the quality of a student's work as excellent or superior.
-
(in some school systems) a symbol designating the first semester of a school year.
-
-
Music.
-
the sixth tone in the scale of C major or the first tone in the relative minor scale, A minor.
-
a string, key, or pipe tuned to this tone.
-
a written or printed note representing this tone.
-
(in the fixed system of solmization) the sixth tone of the scale of C major, called la.
-
the tonality having A as the tonic note.
-
-
Physiology. a major blood group, usually enabling a person whose blood is of this type to donate blood to persons of group A or AB and to receive blood from persons of O or A.
-
Sometimes a the medieval Roman numeral for 50 or 500.
-
Chemistry. (formerly) argon.
-
Chemistry, Physics. mass number.
-
Biochemistry.
-
Logic. Also a universal affirmative.
-
British. a designation for a motion picture recommended as suitable for adults.
-
a proportional shoe width size, narrower than B and wider than AA.
-
a proportional brassiere cup size, smaller than B and larger than AA.
-
a quality rating for a corporate or municipal bond, lower than AA and higher than BBB.
adjective
abbreviation
abbreviation
abbreviation
-
about.
-
acre; acres.
-
active.
-
adjective.
-
alto.
-
ampere; amperes.
-
anonymous.
-
answer.
-
are; ares.
-
Baseball. assist; assists.
abbreviation
abbreviation
abbreviation
-
Absolute.
-
Academy.
-
acre; acres.
-
America.
-
American.
-
angstrom.
-
answer.
-
April.
-
Artillery.
symbol
-
music
-
a note having a frequency of 440 hertz ( A above middle C ) or this value multiplied or divided by any power of 2; the sixth note of the scale of C major
-
a key, string, or pipe producing this note
-
the major or minor key having this note as its tonic
-
-
a human blood type of the ABO group, containing the A antigen
-
(in Britain) a major arterial road
the A3 runs from London to Portsmouth
-
-
a film certified for viewing by anyone, but which contains material that some parents may not wish their children to see
-
( as modifier )
an A film
-
-
mass number
-
the number 10 in hexadecimal notation
-
cards ace
-
chem argon (now superseded by Ar )
-
ampere(s)
-
Also: at. ampere-turn
-
absolute (temperature)
-
(in circuit diagrams) ammeter
-
area
-
(in combination) atomic
an A-bomb
an A-plant
-
chem affinity
-
biochem adenine
-
logic a universal affirmative categorical proposition, such as all men are mortal: often symbolized as SaP Compare E I 2 O 1
-
-
a person whose job is in top management, or who holds a senior administrative or professional position
-
( as modifier ) See also occupation groupings
an A worker
-
abbreviation
determiner
-
used preceding a singular countable noun, if the noun is not previously specified or known
a dog
a terrible disappointment
-
used preceding a proper noun to indicate that a person or thing has some of the qualities of the one named
a Romeo
a Shylock
-
used preceding a noun or determiner of quantity
a cupful
a dozen eggs
a great many
to read a lot
-
used preceding a noun indicating a concrete or abstract thing capable of being divided
half a loaf
a quarter of a minute
-
each or every; per
once a day
fifty pence a pound
-
a certain; one
to change policy at a stroke
a Mr Jones called
-
(preceded by not) any at all
not a hope
symbol
-
acceleration
-
are(s) (metric measure of land)
-
atto-
-
chess See algebraic notation
noun
-
the first letter and first vowel of the modern English alphabet
-
any of several speech sounds represented by this letter, in English as in take, bag, calm, shortage, or cobra
-
Also called: alpha. the first in a series, esp the highest grade or mark, as in an examination
-
from start to finish, thoroughly and in detail
abbreviation
-
acre(s) or acreage
-
America(n)
-
answer
prefix
-
on; in; towards
afoot
abed
aground
aback
-
literary (used before a present participle) in the act or process of
come a-running
go a-hunting
-
in the condition or state of
afloat
alive
asleep
symbol
prefix
verb
preposition
determiner
Grammar
In both spoken and written English the choice of a1 or an 1 is determined by the initial sound of the word that follows. Before a consonant sound, a is used; before a vowel sound, an : a book, a rose; an apple, an opera. Problems arise occasionally when the following word begins with a vowel letter but actually starts with a consonant sound, or vice versa. Some words beginning with the vowel letter u and all words beginning with the vowel letters eu are pronounced with a beginning consonant sound, as if the first letter were y : a union; a European. Some other spellings that begin with a vowel letter may also stand for an initial consonant sound: a ewe; a ewer. The words one and once and all compounds of which they are the first element begin with a w sound: a one-room apartment; a once-famous actor. The names of the consonant letters f, h, l, m, n, r, s, and x are pronounced with a beginning vowel sound. When these letters are used as words or to form words, they are preceded by an : to rent an L-shaped studio; to fly an SST. The names of the vowel letter u and the semivowel letters w and y are pronounced with a beginning consonant sound. When used as words, they are preceded by a : a U-turn; The plumber installed a Y in the line. In some words beginning with the letter h, the h is not pronounced; the words actually begin with a vowel sound: an hour; an honor. When the h is strongly pronounced, as in a stressed syllable at the beginning of a word, it is preceded by a : a history of the Sioux; a hero sandwich. (In former times an was used before strongly pronounced h in a stressed first syllable: an hundred. ) Such adjectives as historic, historical, heroic, and habitual, which begin with an unstressed syllable and often with a silent or weakly pronounced h, are commonly preceded by an, especially in British English. But the use of a rather than an is widespread in both speech and writing: a historical novel; a habitual criminal. Hotel and unique are occasionally preceded by an, but this use is increasingly old-fashioned. Although in some dialects an has yielded to a in all cases, edited writing reflects usage as described above.
Other Word Forms
Noun Inflected Forms
Etymology
Origin of a1
First recorded in 1200–50; Middle English; originally preconsonantal phonetic variant of an 1
Origin of a2
Originally Middle English a, preconsonantal variant of on ( a- 1 ); confused with a 1
Origin of a3
Middle English; unstressed preconsonantal variant of of 1
Origin of a4
First recorded in 1300–50; Middle English; a phonetic variant of have
Origin of a5
First recorded in 1200–50; Middle English a, ha
Origin of a-12
Middle English, late Old English; cf. a 2, nowadays
Origin of a-13
Middle English; see a 3
Origin of a-14
Middle English; Old English a- (unstressed), ǣ-, ā-, ō- (stressed; see abb, woof 1, oakum), rarely or- ( see ordeal), ultimately from unattested Germanic uz- from unstressed Indo-European uss-, from ud-s (these latter two also unattested), akin to out; in some cases confused with a- 4, as in abridge
Origin of a-15
Middle English < Latin ā-, a- (variant of ab- ab- ); in some words < French a- < Latin ab-, as in abridge
Origin of a-16
Middle English, in some words < Middle French a- < Latin ad- prefix or ad preposition ( ad- ), as in abut; in others < Latin a- (variant of ad- ad- ), as in ascend
Origin of -a20
From Latin feminine ending -a, as Claudia, feminine of Claudius; see -a 2
Origin of -a21
Probably generalized from the -a of magnesia
Origin of a.23
< Latin annō, ablative of annus
Origin of a.24
From the Latin word ante
Origin of A.26
< Latin annō, ablative of annus
Origin of A.27
From the Latin word ante
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Franz-Stefan Gady, a Vienna-based defense analyst who makes frequent trips to Ukraine, said Russian infantry have infiltrated Dobropillia, but they are a long way from controlling the city.
From The Wall Street Journal ● Nov. 7, 2026
In the race for District 9, both Jose Ugarte and Estuardo Mazariegos remain locked in a tight contest.
From Los Angeles Times ● Nov. 7, 2026
Russian troops outnumber Ukrainians by about 6-to-1 in the area, said Kyrylo Dubrovskyi, a lieutenant colonel with the First Corps of Ukraine’s National Guard.
From The Wall Street Journal ● Nov. 7, 2026
Barri Worth Girvan, a veteran government employee who ran on a platform of leveraging her experience to advocate for residents, declared victory in the race for Los Angeles City Council’s Third District seat late Friday.
From Los Angeles Times ● Nov. 7, 2026
But if she’s going to succeed in her adopted country—one for which she played such a pivotal wartime role—she’ll have to remind them who she is.
From "At Last She Stood" by Erin Entrada Kelly
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A breakthrough there could open up further advances in the rear of Ukraine’s fortified lines.
From The Wall Street Journal ● Nov. 7, 2026
A neurosurgeon told Isaac's family the only way to save his life was an emergency operation, but that it was one that required blood transfusion.
From BBC ● Nov. 7, 2026
A Volkswagen truck would be a direct run at a segment that Detroit has dominated for more than half a century—one that almost no foreign competitors have been able to crack.
From The Wall Street Journal ● Nov. 7, 2026
A two-time Pro Bowl selection who is just two seasons removed from throwing for 23 touchdowns and three interceptions over 17 games, Herbert has only five touchdowns and a league-high 10 interceptions this year.
From Los Angeles Times ● Nov. 6, 2026
A girl who spoke out for what was right, even when people called her a witch.
From "At Last She Stood" by Erin Entrada Kelly
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In the new study, the research team employed state-of-the-art cryo-electron microscopy techniques to capture nine different states associated with the lipid transport and determine structures at 2.4 to 3.1 Å resolution for these states.
From Science Daily ● Dec. 5, 2023
Danish, an often staccato language spoken by only about six million people and whose alphabet includes the letters Æ, Ø and Å, is perhaps an unlikely choice for pop’s next lingua franca.
From New York Times ● Apr. 19, 2023
“Below 1 Å is almost impossible to reach for cryo-EM,” he says.
From Nature ● Jun. 2, 2020
Note: The length unit angstrom, Å, is often used to represent atomic-scale dimensions and is equivalent to 10−10 m.
From Textbooks ● Feb. 14, 2019
Two or more such β-sheets lie in parallel, 6–12 Å apart.
From Nature ● Nov. 8, 2016
Some songs—such as “A Guid New Year to ane a’ A’”—were widely recognized.
From National Geographic ● Dec. 27, 2023
The Scottish government agreed with a recommendation by Sepa which allows Scottish Water to increase abstraction levels from the Allt a' Mhuilinn burn.
From BBC ● Jun. 17, 2023
Whether all this adds up to some big change a’ coming to City Hall, it’s too soon to say.
From Seattle Times ● May 24, 2023
After a’ dominating Thanksgiving win over Dallas two-plus years ago, Anthony posted a clip of his brother’s leaping pick-six of quarterback Andy Dalton and urged people to vote for Sweat to make the Pro Bowl.
From Washington Times ● Jan. 5, 2023
“Good yer takin’ a taxi, ’stead a’ the subway,” the Cap’n says to us, but it’s me he’s looking at with his one good eye.
From "Challenger Deep" by Neal Shusterman
![]()
And Robert Heath was sort of a- adventurous entrepreneur of a neurologist and psychiatrist.
From Scientific American ● May 4, 2023
That giant thing of spices that looks like a-
From Salon ● Mar. 30, 2019
Average sizes are about 2.0 μm and 1.2 μm along the a- and c-axes, respectively. b, AFM height image and height profiles for the MFI nanosheets.
From Nature ● Mar. 14, 2017
The Israeli grandmaster plays the positional side of a Benko Gambit to perfection, building up great pressure on the a- and b-files while the great Benko bishop strafes the White position from g7.
From Washington Times ● May 12, 2015
"Well, don't do it again. Understand? Not at night There's enough silly talk about beasts, without the litthlus seeing you gliding about like a-" The derisive laughter that rose had fear in it and condemnation.
From "Lord of the Flies" by William Golding
![]()
The ponds, which cover nearly 5,000 hectares, display constantly changing colours -a view he says he never tires of.
From BBC ● Aug. 26, 2025
I don't think the "-e" should eliminate the existing "-o" and the "-a."
From Salon ● Sep. 26, 2022
He needs to grow up or get out -a cancer in the locker room.
From New York Times ● Jan. 9, 2017
Hanks' character -a boy in an adult body - ends up working for a toy company headed by Loggia.
From Reuters ● Dec. 4, 2015
The eyes of some animal peer at me from the neighboring tree -a possum maybe -catching the firelight from the Careers' torches.
From "The Hunger Games" by Suzanne Collins
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"The All Blacks are a classy outfit, and they'll punish you if you're not on your A- game, and at times we weren't," admitted Irish skipper Dan Sheehan.
From BBC ● Jul. 18, 2026
“Mandalorian” got an average grade of A- from audiences, according to market research firm CinemaScore.
From The Wall Street Journal ● May 24, 2026
The difference between an A- and an A+, according to the report, could depend on how much spring precipitation the region receives.
From Los Angeles Times ● May 12, 2024
Normally it’s sort of fun to count the A- , B-, and Z-listers shilling for mayonnaise and sneakers.
From Slate ● Feb. 12, 2024
In 1926 it was decided to build A- and B-blocks on the hill, and in 1929 they were completed, along with the chapel and mess hall.
From "Newjack: Guarding Sing Sing" by Ted Conover
![]()
Find the derivative of the equation in a. and explain its physical meaning.
From Textbooks ● Mar. 30, 2016
Use a. to find the rate at which the volume is changing at t = 1 min.
From Textbooks ● Mar. 30, 2016
From part a. we see that receiving $1.5 million dollars over the course of 20 years is worth $18.693 million dollars in today’s dollars.
From Textbooks ● Mar. 30, 2016
Using a. and b. is the train speeding up or slowing down?
From Textbooks ● Mar. 30, 2016
“He spells it with one a. The two a’s seem a little fancy to his friends.”
From "East of Eden" by John Steinbeck
![]()
An entomologist says: Immo A. Hansen, a medical entomologist at New Mexico State University who studies the physiology of mosquitoes, has very definite opinions about mosquito repellent patches.
From Los Angeles Times ● Nov. 4, 2026
Sofia was visiting family in Hong Kong in July when her nine-month-old son Matthew contracted influenza A. He suffered three cardiac arrests, leaving him unconscious and on a ventilator.
From BBC ● Nov. 4, 2026
"This weekend's numbers are weak. Last Halloween had the same trouble, and this one looks like it's coming in below that," said David A. Gross of Franchise Entertainment Research.
From Barron's ● Nov. 1, 2026
The single specimen of A. aegis came up in 2006 near the Gambier Islands, at the mouth of South Australia’s Spencer Gulf.
From Science Daily ● Oct. 30, 2026
Except they don’t need to because their grades are already beyond an A. I think PPC had to invent a new grading system for them and Maddie.
From "From Twinkle, with Love" by Sandhya Menon
![]()
You know, that’s actually the easiest of all things, if you look, cause it’s such a–
From Slate ● Jan. 22, 2020
The montage ends with a honest rap from Issa: “I don’t want to be here, but my ex won’t take me back. So my broken a– is here, small-talking over apps.”
From Washington Post ● Jul. 28, 2017
We created a– civilian review board, gave them their own detectives.
From Time ● Jan. 17, 2016
MELBER: Now your path here– involved time as a– as a lawyer and a prosecutor.
From MSNBC ● Feb. 12, 2015
But whatever happens, you’ll 240 believe I’ve done my best, won’t you?–even if I’m not a– Promise me straight, you’ll lock up tight every night.”
From Into the Primitive by Robert Ames Bennett
The Cambridge researchers believe comparable weapons could have been responsible for Shanidar A's death.
From Science Daily ● Oct. 31, 2026
Other parents’ choices didn’t cause Najya’s teachers to leave assignments uncorrected, lower expectations, or award A’s for below-grade work.
From The Wall Street Journal ● Sep. 23, 2026
“All achievements — straight A’s at the time — anything that could be rewarded was pooled to funds,” he said, reclining on a patio chair in the shade at Chargers headquarters.
From Los Angeles Times ● Sep. 7, 2026
In May, Harvard University faculty voted to approve a 20% cap on the number of A’s per undergraduate course in an effort to curb grade inflation.
From The Wall Street Journal ● Aug. 11, 2026
For example, if the F sharps are written as G flats, or if the A's are sharp instead of natural, you have a different chord, not an inversion of the same chord.
From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones
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As BBC Radio 1Xtra launches the first UK rap chart show, he's hopeful more grime artists will be inspired to sharpen their pen game.
From BBC ● Nov. 7, 2026
As the sun rises over the Indian Ocean, waves lap onto the golden sands while palm fronds rustle in the cool sea breeze.
From BBC ● Nov. 7, 2026
As soon as Abdy turned her speech toward rage, a faint “preach!” rang from somewhere in the ballroom.
From Los Angeles Times ● Nov. 6, 2026
As the director Barrie Kosky observed in an interview earlier this year, the famous spectacles occupy perhaps 20 minutes of roughly 16 hours of music.
From The Wall Street Journal ● Nov. 6, 2026
As I said, Fireball was always fierce, but our community had made their own choices, and now that its existence was announced online, it was also out of our hands.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
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Like other Romance languages, Spanish divides most endings of nouns into masculine o’s or feminine a’s.
From Washington Times ● Dec. 12, 2021
And then, every fourth January, we’re suddenly expected to say it, to spell it, to know where to place the u’s and a’s.
From New York Times ● Jan. 19, 2017
But there is no doubt who is the original source of the line, and his last name is spelled with two a's.
From Time Magazine Archive
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His accent, a resonant blend of broad a's, clipped consonants and superbly rounded r's, is the same accent he used for credit in Manhattan speakeasies 20 years ago.
From Time Magazine Archive
![]()
“He spells it with one a. The two a’s seem a little fancy to his friends.”
From "East of Eden" by John Steinbeck
![]()
Soon, Hinojosa will be able to appoint commissioners who can act as more of a check on corporate power.
From The Wall Street Journal ● Nov. 7, 2026
Daniel Zingale worked for Newsom as a senior advisor in the governor’s office at the start of his first term.
From Los Angeles Times ● Nov. 7, 2026
"What they heard from the news and everywhere else is not the same as what they see in the country," she says.
From BBC ● Nov. 7, 2026
But many have been shipped to zoos around the world as apart of Beijing's decades-long "panda diplomacy" program to foster foreign ties.
From Barron's ● Nov. 7, 2026
In October 1953, as the deportation hearings to send Joey back to the Philippines gain momentum, Joey writes an editorial for The Star, detailing her uphill battle for citizenship.
From "At Last She Stood" by Erin Entrada Kelly
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