Third-person singular simple present indicative form of underwhelm.(verb)
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Use "underwhelms" in a sentence
"Steve Ballmer keynote underwhelms - but hints that Windows has won internal battle"
"At a sales convention, he underwhelms his colleagues with puffed-up patter, dismisses the idea of giving his hardworking secretary a better job because of the limitations of the "female brain" and then displays his own astute powers of observation by picking up an overserved blonde who steals his wallet."
"Wanna bet come March 25th, if Sucker Punch underwhelms, that the media and behind-the-scenes execs will be crowing about how female action fantasies don't work?"