dissonant (adj.) Look up dissonant at Dictionary.com
early 15c., from Middle French dissonant and directly from Latin dissonantem (nominative dissonans), present participle of dissonare "differ in sound," from dis- "apart" (see dis-) + sonare "to sound, make a noise," "to sound," from PIE *swene-, from root *swen- "to sound" (see sound (n.1)).