The story
- Proto-Indo-European*h₁én
- Proto-Indo-European*h₁énteros
- Latin*interus
- Latinintrā
- Englishintra-
- Latinrēn
- Proto-Indo-European*h₂el-
- Proto-Indo-European*h₂élisder.?
- Late Latinrēnāli
- Englishrenal
- English todayintrarenal
Etymology from Wiktionary, CC BY-SA 4.0.