cac·o·ë·thes (kāk'ō-ē'thēz) n. An irresistible compulsion; a mania.
[Latin cacoēthes, from neuter of Greek kakoēthēs, ill-disposed : kakos, bad; see kakka- in Indo-European roots + ēthos, disposition; see s(w)e- in Indo-European roots.]
"itch for doing something," 1563, from L., from Gk. kakoethes "ill-habit," from kakos "bad" + ethe- "disposition, character" (see ethos). Most famously, in Juvenal's insanabile scribendi cacoethes "incurable passion for writing."