ridiculous, pointless, or nonsensical: full of wild schemes and cockamamie ideas.
Also, cock·a·ma·my.
Origin: ‡ 1940–45, Americanism; in orig. sense, paper strip with an image which could be transferred to the skin when moistened, apparently alteration of decalcomania; sense “ridiculous” probably by association with cock-and-bull story, poppycock, etc.
mod. ridiculous; inconceivable. : That is the most cockamamie thing I ever heard of.
Dictionary of American Slang and Colloquial Expressions by Richard A. Spears.Fourth Edition. Copyright 2007. Published by McGraw Hill.
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