word-forming element of French origin, "one who has a mania for," ultimately from Greek -manes "ardent admirer," related to mania "madness" (see mania).
spelling conventional in 15c.-17c. English to add emphasis to borrowed French nouns ending in stressed -on; also used to represent Italian -one, Spanish -ón; all from Latin -onem. Compare shalloon (1670s) for French chalon, a kind of material used for linings. The ending is used occasionally to form words in English, such as spittoon, quadroon, and some older ones no longer with us, such as shabberoon "disreputable person" (c. 1700).
before vowels electr-, word-forming element meaning "electrical, electricity," Latinized form of Greek ēlektro-, combining form of ēlektron "amber" (see electric). As a stand-alone, formerly often short for electrotype, electroplate.