sin

¹ American  

[sin] / sɪn /

noun

1. transgression of divine law.

   the sin of Adam.

   Synonyms:

   violation, trespass, misdeed

2. any act regarded as such a transgression, especially a willful or deliberate violation of some religious or moral principle.

   Synonyms:

   wickedness, wrong

3. any reprehensible or regrettable action, behavior, lapse, etc.; great fault or offense.

   It's a sin to waste time.

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verb (used without object)

sinned, sinning

1. to commit a sinful act.

   Synonyms:

   trespass, transgress

2. to offend against a principle, standard, etc.

verb (used with object)

sinned, sinning

1. to commit or perform sinfully.

   He sinned his crimes without compunction.

2. to bring, drive, etc., by sinning.

   He sinned his soul to perdition.

sin ² American  

[seen] / sin /

noun

1. the 22nd letter of the Hebrew alphabet.

2. the consonant sound represented by this letter.

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sin ³ American  

abbreviation

Trigonometry.

1. sine.

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sīn ⁴ American  

[seen] / sin /

noun

1. the 12th letter of the Arabic alphabet.

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Sin ⁵ American  

[seen] / sin /

noun

1. the Akkadian god of the moon: the counterpart of the Sumerian Nanna.

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sin ¹ British  

/ saɪn /

abbreviation

1. sine

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sin ² British  

/ sɪn /

preposition

1. a Scot dialect word for since

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SIN ³ British  

abbreviation

1. social insurance number

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sin ⁴ British  

/ siːn /

noun

1. a variant of shin, the 21st letter in the Hebrew alphabet (שׂ), transliterated as S See shin 2

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sin ⁵ British  

/ sɪn /

noun

1. theol

   1. transgression of God's known will or any principle or law regarded as embodying this

   2. the condition of estrangement from God arising from such transgression See also actual sin mortal sin original sin venial sin

2. any serious offence, as against a religious or moral principle

3. any offence against a principle or standard

4. informal (of an unmarried couple) to live together

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verb

1. theol to commit a sin

2. (usually foll by against) to commit an offence (against a person, principle, etc)

sin Scientific  

1. Abbreviation of sine

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sin Idioms  

1. see live in sin; more sinned against than sinning; multitude of sins; ugly as sin; wages of sin.

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Related Words

See crime.

Other Word Forms

• sinlike adjective
• sinner noun
• sinningly adverb
• sinningness noun
• unsinning adjective

Etymology

Origin of sin¹

First recorded before 900; Middle English noun sinne, sin(e), sen(ne), Old English syn(n) “moral or religious offense, misdeed”; akin to German Sünde, Old Norse synd, Latin sōns (inflectional stem sont- ) “guilty,” literally “that man being the one”; the verb is derivative of the noun; the Germanic and Latin forms all being present participle forms of the root es- “to be”; see origin at am ( def. )

Origin of sin²

First recorded in 1895–1900; from Hebrew śīn

Origin of sīn⁴

From Arabic

Explanation

You might not want to be the one at the party who takes the last piece of cake, but then again, it would be a sin to let it sit there, uneaten. A sin is a deeply regrettable action. The most common definition of sin is religious: it's an immoral act against God or divine law. Any serious offense, even if it's not religious, can be called a sin, and so can something less serious if you're talking about it in a joking way, as in, "You've got to buy those shoes — it would be an absolute sin not to." In math, sin is the abbreviation of sine, the trigonometric function.

Example Sentences

In America, Presbyterians preached salvation from sin through the grace of a merciful God.

From The Wall Street Journal • Apr. 11, 2026

That would be considered a mortal sin by the vast majority of football fandom.

From BBC • Mar. 29, 2026

To some in Illinois, letting the storied team leave for Indiana might look like a sin worse than putting ketchup on a Chicago hot dog.

From The Wall Street Journal • Mar. 27, 2026

Nothing will ever undo the original sin, and devoting your life to ruining someone else’s is a loss for both of you.

From Los Angeles Times • Mar. 19, 2026

Though I dress in white like a nun, I feel the stain of sin, of mortality, around me like a bright girdle.

From "Ophelia" by Lisa Klein

Related Words

• crime
• error
• evil
• fault
• guilt
• immorality
• lust
• misdeed
• offense
• shortcoming
• transgression
• violation
• wrong
• wrongdoing