From Proto-Balto-Slavic *damús (“house”), from Proto-Indo-European *domos, from *dṓm. Cognate with Latvian nams, Proto-Slavic *dȍmъ, Latin domus, Ancient Greek δόμος (dómos), Sanskrit दम (dáma). The etymology seems rather secure despite the irregular sound change from *d- to *n-. The original d may be seen in dialectal api̇̀dėmė (“landplot between two homesteads”); compare the more recently formed apýnamė (“area surrounding a house”). The assimilation is most frequently explained as from the zero-grade *dm- > *nm-, with subsequent generalization onto the full-grade stem. Compare Avestan 𐬥𐬨𐬁𐬥𐬀 (nmāna, “house, quarters”). However, the only zero-grade derivative actually attested in Lithuanian, dimstis (“village, estate”) < *dm̥-st-i-, lacks this particular sound change.