knuckle down

verb
knuckled down; knuckling down; knuckles down

Definition of knuckle down

intransitive verb

: to apply oneself earnestly

First Known Use of knuckle down

circa 1864, in the meaning defined above

Keep scrolling for more

Learn More about knuckle down

Statistics for knuckle down

Look-up Popularity

Time Traveler for knuckle down

The first known use of knuckle down was circa 1864

See more words from the same year

Comments on knuckle down

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

WORD OF THE DAY

of or relating to the heavens

Get Word of the Day daily email!

Test Your Vocabulary

Summer 2019 Words of the Day Quiz

  • a-bowl-of-peach-sorbet-with-cut-peaches-next-to-it
  • Which is a synonym of desideratum?
True or False

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

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!