What is a wooden pin, or nail, on which to hang things, as coats, etc. Hence, colloquially and figuratively: A support; a reason; a pretext; as, a peg to hang a claim upon called?

peg — A wooden pin, or nail, on which to hang things, as coats, etc. Hence, colloquially and figuratively: A support; a reason; a pretext; as, a peg to hang a claim upon. (Webster's 1913.)

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