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1. As if struck dumb with astonishment and surprise
   "a circle of policemen stood dumbfounded by her denial of having seen the accident";
   - dumfounded, flabbergasted, stupefied, thunderstruck, dumbstruck, dumbstricken

1. Confuse or leave at a loss because of something complex or difficult to understand
   "These questions dumbfound even the experts";
   - confuse, throw, fox, befuddle, fuddle, bedevil, confound, discombobulate [informal], perplex, vex, stick, get, puzzle, mystify, baffle, beat, pose, bewilder, flummox, stupefy, nonplus, gravel

See also: surprised

Type of: be

Encyclopedia: Dumbfounded