An Etymological Dictionary of the German Language/Annotated/Spieß
Spieß (1.), masculine, ‘spear, lance, pike,’ from Middle High German spieȥ, Old High German spioȥ, masculine, ‘warrior's or hunter's spear’; corresponding to the equivalent. Goth *spiuta- (whence Old French espiet, ‘spear’), Old Icelandic spjót, neuter (in Anglo-Saxon spreót, see Spriet). Cognate terms in the non-Teutonic languages are wanting. — Modern High German Spießgeselle, ‘accomplice,’ literally ‘comrade in arms.’
Spieß (2.), masculine, ‘spit’ (cooking), from the equivalent Middle High German and Old High German spiȥ (genitive spiȥȥes), masculine; corresponding to Dutch spit, Anglo-Saxon spitu, English spit. These cognates, whence the equivalent Romance term, Italian spito, are connected with the adjective spitz, of which Anglo-Saxon spitu is a substantive form. Spieß (French épois) is also used in the sense of ‘dags or croches of a stag,’ a meaning not found in the earlier periods; yet Modern High German Spießer (Old High German spiȥȥo, spizzo, ‘hinnulus’), ‘young stag,’ and the borrowed French term épois, ‘trochings of a stag,’ implies the existence of such a meaning. See spitz.