"shrink, start back, give way; flinch, wince, dodge," c. 1200, extended sense from Old English blencan "deceive, cheat" (obsolete in the original sense), from Proto-Germanic *blenk- "to shine, dazzle, blind" (source also of Old Norse blekkja "delude"), from PIE root *bhel- (1) "to shine, flash, burn," also "shining white." Related: Blenched; blenching.
"mislead by false appearance or statement," c. 1300, from Old French decevoir "to deceive" (12c., Modern French décevoir), from Latin decipere "to ensnare, take in, beguile, cheat," from de "from" or pejorative (see de-) + combining form of capere "to take," from PIE root *kap- "to grasp." Related: Deceived; deceiver; deceiving.
"swindler, impostor," c. 1600; also "one easily cheated" (1640s); "a swindle, trick, sham, imposition" (1708), an obsolete word said to be from Turkish chaush "sergeant, herald, messenger," but the sense connection is obscure. Century Dictionary says the Turkish word is via Arabic khawas from Hindi khawas "an attendant." Also used as a verb, "to cheat, swindle" (1650s).
"to cheat, trick, swindle," 1703, originally a slang or cant word, of unknown origin. Perhaps Scottish from bombaze, bumbaze "confound, perplex," or related to bombast, or related to French embabouiner "to make a fool (literally 'baboon') of." Wedgwood suggests Italian bambolo, bamboccio, bambocciolo "a young babe," extended by metonymy to mean "an old dotard or babish gull." Related: Bamboozled; bamboozler; bamboozling. As a noun from 1703.