Other forms: crackpots
A crackpot is somebody with wild and eccentric ideas. A crackpot theory, some crackpot on the radio, crackpot schemes.
It attaches to the idea as often as to the person, and a crackpot theory is one nobody serious will engage with. It is mild as insults go, and the pot in it is the head — a crackpot is somebody with a crack in it.
1nouncrackpotSomebody with wild and eccentric ideas.
“Everyone thought he was a crackpot when he said he could build a car that ran on water.”
crackpot is an insult.
From crack plus pot, an old slang word for the head, recorded from the nineteenth century.
Mostly likely a back-etymology of pot, to form crack + pot. Originally, from crack + pate. Compare typologically чо́кнутый (< чо́каться, onomatopoeic), see crack for the further typology.
Etymology from Wiktionary, CC BY-SA