dormio.

Etymology tree Proto-Indo-European *drem- Proto-Indo-European *-yéti Proto-Indo-European *dr̥m-yé-ti Proto-Italic *dormiō Latin dormio Inherited from Proto-Italic *dormiō, from Proto-Indo-European *dr̥m-yé-ti, from *drem- (“to sleep”) + *-yéti. The sound law *-mj- > Proto-Italic *-nj did not affect this term likely as a consequence of the rules of PIE syllabification. The sequence *gʷm̥y-, with a syllabic *m̥, yields veni-, whereas *dr̥my-—with a syllabic *r̥—yields dormi-. Had the original PIE form been syllabified as *drm̥y-, the expected Latin outcome would have been **dreniō. Cognates include Old Church Slavonic дрѣмати (drěmati, “to drowse, doze”), Russian дрема́ть (dremátʹ), Sanskrit द्राति (drāti, “to sleep”), Ancient Greek δαρθάνω (darthánō, “to sleep”).