In this contribution I propose to etymologically connect Vedic yóni-'safe place; bed, nest; womb' and Avestan yaona-'safe place' with Greek εὐνή 'bed; lair' as well as Old Irish úam 'cave; lair, den'. I derive these words from a PIE formation *(H)i̯ eumn-V-meaning 'nest, private place' and derived from the root *(H)i̯ eu-'to separate, set apart' (Vedic pres. yuyóti). Furthermore, it is argued that the Greek adjective εὖνις 'bereft' as well as the noun ὑμήν 'membrane' derive from the same root.In a recent contribution, Oettinger (2016) has discussed the semantics of Vedic yóni-. He asserts that the concrete meaning 'womb' is primary, and that meanings like 'resting place, bed, seat, abode' arose by metaphorical extension. The etymology of yóni-, however, remains unclear 2 and we must also take into account that the denotation 'womb' may have arisen as a euphemism for a woman's private parts.In the following pages, I elaborate in more detail an etymological proposal already made in my doctoral dissertation (van Beek 2013: 316-319). 3 Compared to this previous treatment, various details are added or modified in the present paper: I discuss the consequences of this new etymology for the issue of the double outcome of initial yod in Greek, and also deal extensively with the differences in gender and stem formation (i-stem versus thematic stem) between the attested forms. As for the root etymology, I now propose a derivation from PIE *(H)i̯ eu-'to separate' (Vedic pres. yuyóti). Finally, it is argued that the adjective εὖνις 'bereft' derives from the same root and thus may have an identical origin with Vedic yóni-.