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interior m. (Adjective, Noun) "interior"
15th cent. An adjectival from Latin interior 'id.' From Proto-Italic *n̥tero- 'id.' From Proto-Indo-European *h1én-tero- 'id.,' a compound of *h1en "in" (whence en) and *-tero-, a comparative suffix (see -tr-).
Indo-European
Celtic
Celtiberian entara, Old Irish eter, Old Welsh ithr, Breton etre, Cornish ynter
Germanic
Gothic undar "between," Old Norse undorn "midday," Old Saxon under "before midday," Old High German untar "between," Old English under "before midday" (English in)
Albanian
Albanian ndër
Balto-Slavic
Lithuanian į́sčios "womb," Latvian ìekšas "entrails," Old Prussian instran "fat"
Hellenic
Ancient Greek ἔντερα (éntera) "intestines"
Armenian
Armenian ənderk' "intestines"
Indo-Iranian
Sanskrit antár, Old Avestan aṇtarə̄̆