daff

Etymology

From Middle English daf, daffe (“fool, idiot”), from Old Norse daufr (“deaf, stupid”), from Proto-Germanic *daubaz (“deaf, stunned”), from Proto-Indo-European *dʰewbʰ- (“to whisk, whirl, smoke, be obscure”). Doublet of deaf, dof, and dowf. Cognate with Swedish döv (“deaf”), Danish døv (“deaf, stupid”). More at deaf.