TOMFOOL
fool, sap, saphead, muggins, tomfool
(noun) a person who lacks good judgment
Source: WordNet® 3.1
Etymology
Noun
tomfool (plural tomfools)
a silly or stupid person, especially a boy or man.
(Caribbean, colloquial) Any of various tyrant flycatchers viewed as foolishly confiding.
Adjective
tomfool (comparative more tomfool, superlative most tomfool)
silly or stupid.
Verb
tomfool (third-person singular simple present tomfools, present participle tomfooling, simple past and past participle tomfooled)
(intransitive) To act foolishly.
Source: Wiktionary
Tom"fool`, n. Etym: [Tom (see Tomboy) + fool.]
Definition: A great fool; a trifler.
Source: Webster’s Unabridged Dictionary 1913 Edition