Question: what is the meaning of the idiomatic expression square peg in a round hole?
Answer: square peg in a round hole. Also, round peg in a square hole. A misfit, especially a person unsuited for a position or activity. For example, Ruth doesn't have the finesse for this job; she's a round peg in a square hole. This idiom, with its graphic image of something that cannot fit, dates from about 1800.