take (someone) down a peg, to

take someone down a peg (or two)

 and take someone down a notch (or two); knock someone down a peg (or two); knock someone down a notch (or two)
Fig. to reprimand someone who is acting too arrogant. The teacher's scolding took Bob down a notch or two. He was so rude that someone was bound to knock him down a peg or two.
See also: down, peg, take

take (someone) down a peg

To reduce the pride of; humble.
See also: down, peg, take

take (someone) down a peg, to

To deflate or humble someone. This term alludes to lowering a ship’s colors, which were maneuvered by means of pegs. The higher the colors were flown, the greater the honor. The term was already being transferred by 1664, when Samuel Butler wrote (Hudibras), “Trepanned your party with intrigue, And took your grandees down a peg.” John Ray’s Proverbs (1678) defined it as “to remind upstarts of their former condition.” It is still widely used.
See also: down, take
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