early 14c., "symbolization, representation," from Old French significacion and directly from Latin significationem (nominative significatio) "a signifying, indication, expression, sign, token, meaning, emphasis," noun of action from past participle stem of significare "make known, indicate" (see signify). From late 14c. as "meaning" (of a word, etc.). Old English used getacnung as a loan-translation of Latin significatio.
child's name for a horse, also a toy horse or rocking horse, 1540s, a nursery word of uncertain signification.
short for rhinoceros, 1884. As slang for "cash" (also rino) 1680s, but the signification is now unknown. Hence cant rhinocerial "rich."
"most important piece or feature," 1831, from French pièce de résistance, originally "the most substantial dish in a meal." Literally "piece of resistance;" there seems to be disagreement as to the exact signification.