peg (one) for (something)

peg (one) for (something)

To believe or consider that one definitely is a certain type of person or thing. I pegged her for a total bore when she first started working here, but since getting to know her, she's actually pretty interesting. I'm disappointed, Jake—I never pegged you for a quitter.
See also: peg
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
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