Little did I envision the difficulties encountered in building a list of -cide words. In general, such words are a combined form, signifying 'killer' or 'killing' (from the Latin caedere, to cut or kill). There are, however, three groups of exceptions: (1) development from other, similar roots; (2) neologisms, many of which are nonsensical; and (3) accidents of etymology.
Scheetz, George H.
Word Ways: Vol. 12
, Article 8.
Available at: http://digitalcommons.butler.edu/wordways/vol12/iss1/8