Crackpot

[krak-pot] /ˈkrækˌpɒt/ Informal.

noun
1.
a person who is eccentric, unrealistic, or fanatical.
adjective
2.
eccentric; impractical; fanatical:
crackpot ideas.
/ˈkrækˌpɒt/
noun
1.
an eccentric person; crank
adjective
2.
(usually prenominal) eccentric; crazy
n.

“mentally unbalanced person,” by 1900, probably from crack + pot (n.1) in a slang sense of “head.” Cf. crack-brain “crazy fellow” (late 16c.). Earlier it was used in a slang sense “a small-time big-shot” (1883), and by medical doctors in reference to a “metallic chinking sometimes heard when percussion is made over a cavity which communicates with a bronchus.”

adjective

: my colleague’s crackpot notions

noun

A crazy idiot; an addled fool; eccentric: He’s a crackpot about flying saucers (1883+)

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