An Etymological Dictionary of the German Language/Annotated/blank

by Friedrich Kluge

blank, adjective, ‘bright, drawn (of a sword),’ from the Middle High German blanc, Old High German blanch, ‘gleaming, white, resplendently beautiful.’ Compare English blank (‘white’), (Anglo-Saxon blanca, blonca, Old Icelandic blakkr, ‘white or grey horse’); related to Old Icelandic blakra, ‘to gleam’; formed by gradation from the root blek in Blitz (compare also blecken). The adjective made its way into Romance (Italian bianco, French blanc), whence Blankett with a Romance suffix; compare also blasen. The less frequent blink — a recent formation from the verb — is found as a parallel form to blank in Modern High German.