MONOMANIAmonomania (mon-[schwa]-may-nee-[schwa]). Insanity about some particular subject or class of subjects, usu. manifested by a single insane delusion. ? A will made by someone suffering from this condition is usu. held valid unless the evidence shows that particular provisions in the will were influenced by the insane delusion. [Cases: Mental Health
3. 1.] ¡ª monomaniacal, adj. ¡ª monomaniac, n.