Emily Dickinson Lexicon

FOOL, n.¹ [Fr. fol, fou; It. folle, mad, foolish; Ice. fol; Arm. foll; W. fol, round, blunt, foolish, vain; fwl, a fool, a blunt one, a stupid one; Russ. phalia. It would seem from the Welsh that the primary sense of the adjective is thick, blunt, lumpish. Heb. תפל.]

1. One who is destitute of reason, or the common powers of understanding; an idiot. Some persons are born fools, and are called natural fools; others may become fools by some injury done to the brain.
2. In common language, a person who is somewhat deficient in intellect, but not an idiot; or a person who acts absurdly; one who does not exercise his reason; one who pursues a course contrary to the dictates of wisdom. Experience keeps a dear school, but fools will learn in no other. Franklin.
3. In Scripture, fool is often used for a wicked or depraved person; one who acts contrary to sound wisdom in his moral deportment; one who follows his own inclinations, who prefers trifling and temporary pleasures to the service of God and eternal happiness. The fool hath said in his heart, there is no God. Ps. xiv.
4. A weak Christian; a godly person who has much remaining sin and unbelief. O fools, and slow of heart to believe all the prophets have written. Luke xxiv. Also, one who is accounted or called a fool by ungodly men. I Cor. iv. 10.
5. A term of indignity and reproach. To be thought knowing, you must first put the fool upoa all mankind. Dryden.
6. One who counterfeits folly; a buffoon; as, a king's fool. I scorn, although their drudge, to be their fool or jester. Milton. To play the fool, to act the buffoon; to jest; to make sport. #2. To act like one void of understanding. To put the fool on, to impose on; to delude. To make a fool of, to frustrate; to defeat; to disappoint.