Cockamamie

Alternative forms

 * cockamamy or cockamammy

Etymology
From French; derived from décalcomanie, a word used to describing the popular use of children's rub-on tattoos or other transfer decals. Sometimes erroneously claimed to derive from Yiddish

Adjective

 * 1) foolish, silly
 * 2) trifling
 * Do not give any more cockamamie reasons for failing to complete your assignment.

Thesaurus
absurd, beyond belief, bizarre, crazy, extravagant, fantastic, foolish, grotesque, high-flown, incredible, laughable, ludicrous, monstrous, nonsensical, outrageous, outre, poppycockish, preposterous, ridiculous, weird, wild

Synonyms

 * goofy
 * sappy
 * unreasonable
 * wacky
 * zany