Found 2 items, similar to crackbrained.
English → English (WordNet) Definition: crackbrained crackbrained adj : insanely irresponsible; “an idiotic idea” [syn: idiotic]
English → English (gcide) Definition: crackbrained crackbrained \crackbrained\, Crack-brained \Crack"-brained`\(-br[=a]nd`), a. Having an impaired intellect; whimsical; extremely foolish; crazy; as, crackbrained notions. --Pope. Syn: idiotic. [1913 Webster + WordNet 1.5 +PJC]