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eff

abbreviation

Definition of eff

efficiency

Seen and Heard

What made you want to look up eff? Please tell us where you read or heard it (including the quote, if possible).

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WORD OF THE DAY

shofar

play

a ram's-horn trumpet used in Judaism

Words at Play

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The Ambiguity of Pushing 'Up' and 'Back'

When you push a meeting, where does it go?

Silent Letters

When each letter can be seen but not heard

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'So Long': A Common But Mysterious Goodbye

Its origins are surprisingly murky.

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"Immune to" or "Immune from"?

Nobody is immune to this question.

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).

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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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True or False?

Test your knowledge - and maybe learn something along the way.

Take the quiz

SCRABBLE® Sprint

SCRABBLE® Sprint

SCRABBLE® fans, sharpen your skills!

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