The Collaborative International Dictionary of English v.0.48:

Cyanide \Cy"a*nide\ (s?"?-n?d or -n?d; 104), n. [Cf. F. cyanide.
   See Cyanic.] (Chem.)
   A compound formed by the union of cyanogen with an element or
   radical.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cyanide
    n 1: any of a class of organic compounds containing the cyano
         radical -CN [syn: nitrile, nitril, cyanide]
    2: an extremely poisonous salt of hydrocyanic acid