An Etymological Dictionary of the German Language/Annotated/blöde
blöde, adjective, ‘weak, dim-sighted, imbecile,’ from Middle High German blœde, ‘infirm, weak, tender, timid,’ Old High German blôdi, Old Saxon blôði, ‘timid.’ Compare Anglo-Saxon bleáþ, ‘weak,’ Old Icelandic blauþr; Gothic *blauþus, ‘weak, powerless,’ may be inferred from its derivative weak verb blauþjan, ‘to render powerless, invalid, to abolish.’ According to the permutation of consonants, the pre-Teutonic form of the adjective may have been bhláutu-s, with the primary meaning ‘powerless, weak.’ Yet the stem cannot be traced farther back. From this word French éblouir, ‘to dazzle,’ is borrowed.