One doesn't require an expert to tell one what one already knows.

plural of Spanish donkey

A torture device consisting of a very narrow vertical surface where the victim is supposed to sit with heavy objects attached to their feet.

plural of dead donkey

(chiefly UK) Something done habitually or according to social norms, expectations, etc.

A hand gesture made by placing the thumbs above each ear and waving the index fingers in unison; used to express derision.

(Internet slang) Said to urge another not to respond to disruptive attention-seeking behavior, particularly in online contexts, by pointing out any such response is likely to be counterproductive.

Alternative form of you don't dip your pen in company ink

Indicates that the speaker has no interest or emotional investment in the topic at hand.

(slang, idiomatic, humorous) Used to reserve the right to chat up an attractive woman who is with an unattractive woman.