Dictionary.com

knock oneself out

Save This Word!

1

Make a great effort, as in I was knocking myself out to finish on time. This expression also is put negatively, Don't knock yourself out, meaning “don't exert yourself; it's not worth that much effort.” [c. 1930]

2

Enjoy yourself, have a good time, as in You're off to Europe? Knock yourself out. [Slang; mid-1900s] Both usages allude to knocking oneself unconscious (see knock out). For a synonym see break one's ass.

QUIZZES

QUIZ YOURSELF ON THE 12 TYPES OF VERB TENSES!

Loosen up your grammar muscles because it’s time to test your knowledge on verb tenses!
Question 1 of 6
The verb tenses can be split into which 3 primary categories?

Meet Grammar Coach

Write or paste your essay, email, or story into Grammar Coach and get grammar helpImprove Your Writing

Meet Grammar Coach

Improve Your Writing
Write or paste your essay, email, or story into Grammar Coach and get grammar help
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.

How to use knock oneself out in a sentence

FEEDBACK