Full Definition of FACET. 1. : a small plane surface (as on a cut gem) â see brilliant illustration. 2. : any of the definable aspects that make up a subject (as of contemplation) or an object (as of consideration). 3. : the external corneal surface of an ommatidium.
Definition of cyanide. 1  1 : a compound of cyanogen with a more electropositive element or group: such asa : potassium cyanideb : sodium cyanide. 2  2 : cyanogen 1.
Wiktionary(0.00 / 0 votes)Rate this definition: 1  cyanide(Noun) Any compound containing the -Cu2261N radical or the Cu2261N anion. 2  cyanide(Noun) potassium cyanide - a water soluble poison. 3  cyanide(Noun) hydrogen cyanide, or cyanide gas - a poisonous gas.