The story
- Proto-Indo-European*h₁én
- Proto-Indo-European*h₁entér
- Proto-Indo-European*h₂én
- Proto-Indo-European*dʰeh₁-?
- Proto-Indo-European*(H)n̥dʰí
- Proto-Indo-European*(H)n̥dʰér
- Proto-Germanic*under
- Proto-West Germanic*undar
- Old Englishunder-
- Middle Englishunder-
- Englishunder-
- Proto-Indo-European*dʰregʰ-der.?
- Latintrahere
- Vulgar Latin*tragīnāre
- Old Frenchtraïner
- Old Frenchtrain
- Middle Englishtrayne
- Englishtrain
- Englishtrained
- English todayundertrained
Etymology from Wiktionary, CC BY-SA 4.0.