1. square peg in a round hole - Noun
2. square peg in a round hole - Phrase
square peg in a round hole (plural square pegs in round holes)
(idiomatic) Something or someone that does not fit well or at all; something that will not succeed as attempted, except possibly with much force and effort, or alteration of either the peg or the hole or both beyond recognition.
But then I have always been somewhat of a square peg in a round hole. Cressida Cowell
That's me. I can be me a bit at home, but I'm kind of like a square peg in a round hole. Mick Ralphs
It's my job not always to put square pegs in square holes but sometimes to put the odd square peg in a round hole. Phil Brown (footballer)