See flinch in Webster's New World Roget's A-Z Thesaurus II
verb
To draw away involuntarily, usually out of fear or disgust:
blench1, cringe, quail, recoil, shrink, shy1, start, wince. See approach, seek
noun
An act of drawing back in an involuntary or instinctive fashion:
cringe, recoil, shrink, wince. See approach, seek
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