Synonyms of the word 
UNDERRATE → MISJUDGE - UNDERESTIMATE
underrate
- v. (transitive) to underestimate; to make too low a rate or estimate.
- n. A price less than the value.
misjudge
- v. To make an error in judging, to incorrectly assess.
underestimate
- v. (transitive) To perceive (someone or something) as having a lower value, quantity, worth, etc., than what…
- n. An estimate or perception that is too low.
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