not know one's arse from one's elbowidiom
Definition of not know one's arse from one's elbow
British, informal + impolite
: to know nothing : to be stupid Don't take his word for it—he doesn't know his arse from his elbow.
Love words? Need even more definitions?Merriam-Webster unabridged
Words at Play
- The Wayward Cousins of 'Irregardless'
- Different Words for Luggage and Baggage
- Rapping on 'Bad Rap' and 'Bad Rep' (and 'Bad Wrap')
- 'Confuzzled': A Not So Confusing Definition
Ask the Editors
- On Contractions of Multiple Words
- A Look at Uncommon Onomatopoeia
- Is Singular 'They' a Better Choice?
- Time Traveler Quiz: Which Word Came First? Take the quiz
- Slippery Words Quiz—Changing with the Times Take the quiz
- True or False? Take the quiz
- Word Winder's CrossWinder Play the game