diacritic (adj.) Look up diacritic at Dictionary.com
1690s, of sounds, from Greek diakritikos "that separates or distinguishes," from diakrinein "to separate one from another," from dia- (see dia-) + krinein "to separate, decide, judge" (from PIE root *krei- "to sieve," thus "discriminate, distinguish"). As a noun, from 1866. Related: Diacritical.