Cachinnation
Pronunciation : Cach`in*na"tion
Part of Speech : n.
Etymology : [L. cachinnatio, fr. cachinnare to laugh aloud, cf Gr.
Definition : Defn: Loud or immoderate laughter; -- often a symptom of hysterical or maniacal affections. Hideous grimaces . . . attended this unusual cachinnation. Sir W. Scott.
Source : Webster's Unabridged Dictionary, 1913