THESAURUS
take aback
abash, appall, astound, bowl down, bowl over, confound, discomfit, disconcert, dismay, electrify, frighten, jar, jolt, put out, shake, shock, stagger, startle, stun
ROGET THESAURUS
take aback
Inexpectation
VB
not expect, be taken by surprise, start, miscalculate, not bargain for, come upon, fall upon, be unexpected, come unawares, turn up, pop, drop from the clouds, come upon one, burst upon one, flash upon one, bounce upon one, steal upon one, creep upon one, come like a thunder clap, burst like a thunderclap, thunder bolt, take by surprise, catch by surprise, catch unawares, catch napping, yach, pounce upon, spring a mine upon, surprise, startle,
take aback, electrify, stun, stagger, take away one's breath, throw off one's guard, astonish, dumbfound.