*-assuz

From earlier *-at-tuz, from *-atjaną + *-tuz (*-þuz, from Proto-Indo-European *-tu-s). The extension *-at- was reanalyzed by speakers as part of the root, and the word was then reformulated as a tu-stem. The *-tt- coronal cluster produced *-ss- (via an intermediate *-ts-) (Fulk 2018: 113). This suffix was likely already being used in Proto-Germanic as a general noun-forming suffix rather than being strictly deverbal, as evidenced by Gothic 𐌹𐌱𐌽𐌰𐍃𐍃𐌿𐍃 (ibnassus), which seemingly came from 𐌹𐌱𐌽𐍃 (ibns), rather than from a verb *𐌹𐌱𐌽𐌾𐌰𐌽 (*ibnjan, attested as 𐌲𐌰𐌹𐌱𐌽𐌾𐌰𐌽 (gaibnjan)) (Ringe 2017: 325). Closely related to *-inassuz and probably related to *-ōþuz.