i
1 American-
Also called imaginary unit. the imaginary number .
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a unit vector on the x -axis of a coordinate system.
noun
plural
I's, Is, i's, is-
the ninth letter of the English alphabet, a vowel.
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any spoken sound represented by the letter I or i, as in big, nice, or ski.
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something having the shape of an I.
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a written or printed representation of the letter I or i.
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a device, as a printer's type, for reproducing the letter I or i.
pronoun
nominative
I,possessive
my, mine,objective
me,plural nominative
we,possessive
our, ours,objective
usnoun
plural
I's-
(used to denote the narrator of a literary work written in the first person singular.)
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Metaphysics. the ego.
abbreviation
-
the ninth in order or in a series.
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(sometimes lowercase) the Roman numeral for 1.
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Chemistry. iodine.
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Biochemistry. isoleucine.
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Electricity. current.
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Logic. particular affirmative.
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(italics) isotopic spin.
abbreviation
-
imperator.
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incisor.
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interest.
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intransitive.
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island.
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isle; isles.
abbreviation
-
Independent.
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Island; Islands.
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Isle; Isles.
abbreviation
-
International
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Island or Isle
noun
-
the ninth letter and third vowel of the modern English alphabet
-
any of several speech sounds represented by this letter, in English as in bite or hit
-
-
something shaped like an I
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( in combination )
an I-beam
-
-
to pay meticulous attention to detail
symbol
pronoun
symbol
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chem iodine
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physics current
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physics isospin
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logic a particular affirmative categorial statement, such as some men are married, often symbolized as SiP Compare A E O 1
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one See Roman numerals
abbreviation
suffix
Grammar
See me.
Etymology
Origin of I
First recorded before 900; Middle English ik, ich, i, Old English ic, ih; cognate with Gothic ik, German ich, Old Norse ek, Latin ego, Greek egṓ, Old Church Slavonic azŭ, Lithuanian aš, Sanskrit ahám
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.
"This information will prevent the overtreatment of low-risk patients, thereby limiting side effects and unnecessary costs, while intensifying the monitoring and treatment of those at high risk," says Ariel Ruiz i Altaba.
From Science Daily • Mar. 21, 2026
“I think i just like the idea of throwing something down the lane,” says Belmonte, “watching it and then having it come back to you and just doing that over and over.”
From Los Angeles Times • Mar. 16, 2026
In August 2010, a month before Epstein brought the four women to Buckingham Palace, he emailed Andrew: “I have a friend who i think you might enjoy having dinner with.”
From The Wall Street Journal • Feb. 17, 2026
DMGT, whose titles also include the i Paper, the New Scientist and Metro, agreed to buy the Telegraph in November after years of uncertainty over the paper's future owner.
From BBC • Feb. 12, 2026
I only know 3 people who do little circles instead of dots over the letter i.
From "The Curious Incident of the Dog in the Night-Time" by Mark Haddon
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.