köken: From Middle English roste, from Old French rost, roste, from the verb rostir, from Frankish *raustijan (“to roast”), from Proto-Indo-European *Hrews- (“to crackle, roast”).
From Proto-Italic *assos (“dried, roasted”), ultimately from Proto-Indo-European *h₂ed- (“to dry”); see Ancient Greek ἄζω (ázō, “to dry”) for more on the root and its reconstruction.