An Etymological Dictionary of the German Language/Annotated/Stimme

Stimme, feminine, ‘voice, sound,’ from the equivalent Middle High German stimme, Old High German stimma, feminine, of which the older variant, stimna, corresponds to Old Saxon stëmna (stëmma), Anglo-Saxon stëmn, stefn (English dialectic steven, ‘noise, cry’), Gothic stibna, ‘voice.’ It is uncertain whether *stebnô- or stibnô- is the older form. The connection with Greek στόμα, ‘mouth,’ is dubious.