not

¹ American  

[not] / nɒt /

adverb

1. (used to express negation, denial, refusal, or prohibition).

   You must not do that. It's not far from here.

2. U.S. Slang. (used jocularly as a postpositive interjection to indicate that a previous statement is untrue).

   I just love working overtime without pay. Not!

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idioms

1. not so much, (an expression of dismissive scorn, ambivalence, or skepticism).

   Attractive? Yes. Smart? Not so much.

   Is the world coming to an end? Yeah, not so much.

NOT ² American  

[not] / nɒt /

noun

1. a Boolean operator that returns a positive result if its operand is negative and a negative result if its operand is positive.

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not- ³ American  

1. variant of noto- before a vowel.

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not ¹ British  

/ nɒt /

adverb

1. 1. used to negate the sentence, phrase, or word that it modifies

      I will not stand for it

   2. ( in combination )

      they cannot go

2. Also (archaic): not but what.  (conjunction) which is not to say or suppose that

   I expect to lose the game — not that I mind

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1. used to indicate denial, negation, or refusal

   certainly not

not- ² British  

combining form

1. a variant of noto-

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not More Idioms  

More idioms and phrases containing not

• (not a) Chinaman's chance
• (not to) sneeze at
• (not) all there
• (not) at all
• (not) in the least
• (not) in the mood
• (not) move a muscle
• (not) take no for an answer
• (not) the half of it
• (not) turn a hair
• all that glitters is not gold
• believe it or not
• can't
• caught dead, not be
• coming or going, not know if
• couldn't
• do as I say (not as I do)
• game is not worth the candle
• heart (not) in it
• hold one's breath, not
• it's (not) your funeral
• last but not least
• like as not
• living soul, not a
• mince matters, not to
• more often than not
• no problem (not to worry)
• two wrongs do not make a right
• waste not, want not
• whether or not
• without a (not a) leg to stand on
• won't (will not) hear of
• wouldn't

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Etymology

Origin of not

First recorded in 1275–1325; Middle English; weak variant of nought

Explanation

The adverb not is used for negation. Do you like drinking cod liver oil? No, I do not like drinking cod liver oil. Not is a powerful word. When Hamlet says "to be or not to be," he is questioning whether he should live or die, the inverse of living. Just be careful of what's called a "double negative," where you use not with another negating word and end up negating your negation. If you say you don't know nothing about something, that means you do know something. Not is often contracted as in don't, or isn't.

Example Sentences

The decision not to carry out fresh attacks on Iran but continue to prevent its ships from passing through the Strait -- a major sticking point between the rivals -- left traders awaiting clearer developments.

From Barron's • Apr. 22, 2026

Fiji's ambassador to the United Nations, Filipo Tarakinikini, wrote on social media on Monday that the Vuda coast north of Nadi "must not become the Pacific's ashtray".

From Barron's • Apr. 22, 2026

"It is not a project intended to import waste from overseas," he said.

From Barron's • Apr. 22, 2026

The game is not lost for the Europeans, in Foundoukidis's view, "as long as traditional manufacturers step up their competitiveness efforts to catch up with their Chinese rivals over the next two or three years".

From Barron's • Apr. 22, 2026

“It’s not, but . . .” I glance at the time on my phone and groan.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith