Logaids

A chronic disease in which the infected patient feels an incessant and urgent need to vocalize various profanities, the most prominent being "penis." It is spread, literally, by word of mouth; once an innocent bystander hears an infect person yell "penis" for no apparent reason, they will succumb to the irresistible urge to reply in kind. (True to scientific nomenclature, the name is a portmanteau of the progenitor and a similarly fast-spreading disease.)