flinch

Concise Oxford English Dictionary © 2008 Oxford University Press:
flinch/flɪntʃ/

▶verb

• 1 make a quick, nervous movement as an instinctive reaction to fear or pain.

• 2 (flinch from) avoid through fear or anxiety.

▶noun an act of flinching.

– derivatives
flincher noun,
flinching adjective,
flinchingly adverb.

– origin C16 (in the sense ‘slink or sneak off’): from OFr. flenchir ‘turn aside’, of W. Gmc origin.