not know one's arse from one's elbow

idiom

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.

Dictionary Entries Near not know one's arse from one's elbow

Cite this Entry

“Not know one's arse from one's elbow.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/not%20know%20one%27s%20arse%20from%20one%27s%20elbow. Accessed 12 Apr. 2024.

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