SINCE 1828

An Encyclopædia Britannica Company

certainly not

Definition of certainly not

:not at all

"Did I offend you?" "Oh, certainly not."

Word by Word Definitions

certainly play

: in a manner that is certain : with certainty
: it is certain that : assuredly

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Seen and Heard

What made you want to look up certainly not? Please tell us where you read or heard it (including the quote, if possible).

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WORD OF THE DAY

legerity

play

alert quickness of mind or body

Words at Play

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Breathing Life Into 'Inspire'

The word's origins are quite literal

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Let's Talk 'Tea'

Spill it, sip it: just make it hot.

8 Words and Phrases from Boxing and Wrestling

Common terms that come from boxing and wrestling

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The Ambiguity of Pushing 'Up' and 'Back'

When you push a meeting, where does it go?

Ask the Editors

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Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

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Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals

Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

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Merriam-Webster's New Words Quiz—Fall 2017 Edition!

You're going to have to memorize the dictionary again.

Take the quiz

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Challenging Vocabulary Quiz Returns!

No tricks, just difficult words.

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How Strong Is Your Vocabulary?

How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

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Word Winder's CrossWinder

Word Winder's CrossWinder

A game of winding words.

Play the game