Etymology: Middle English, from Anglo-French fol, from Late Latin follis, from Latin, bellows, bag; akin to Old High German bolla blister, balg bag — more at belly
Date: 13th century
1. a person lacking in judgment or prudence
a. a retainer formerly kept in great households to provide casual entertainment and commonly dressed in motley with cap, bells, and bauble
b. one who is victimized or made to appear foolish ; dupe
a. a harmlessly deranged person or one lacking in common powers of understanding
b. one with a marked propensity or fondness for something <a dancing fool> <a fool for candy> 4. a cold dessert of pureed fruit mixed with whipped cream or custard II. adjective Date: 13th century foolish, silly <barking its fool head off> III. verb Date: 1593 intransitive verb 1. a. to behave foolishly <told the children to stop their fooling> — often used with around b. to meddle, tamper, or experiment especially thoughtlessly or ignorantly <don't fool with that gun> — often used with around 2. a. to play or improvise a comic role b. to speak in jest ; joke <I was only fooling> 3. to contend or fight without serious intent or with less than full strength ; toy <a dangerous man to fool with> transitive verb 1. to make a fool of ; deceive 2. obsolete infatuate 3. to spend on trifles or without advantage ; fritter — used with away
New Collegiate Dictionary. 2001.