The story
- Proto-Indo-European*terh₂-
- Proto-Indo-European*térh₂t
- Proto-Indo-European*tr̥h₂ónts
- Proto-Indo-European*tr̥h₂n̥ts
- Proto-Italic*trāns
- Proto-Italic*trāns-
- Latintrāns-
- Ancient Greekμορφή (morphḗ)der.?
- Latinfōrma
- Latinfōrmō
- Latintransformo
- Old Frenchtransformer
- Middle Frenchtransfourmer
- Middle Englishtransformen
- English todaytransform
From Middle English transformen, from Old French transformer, from Latin transformo, transformare, from trans (“across”, preposition) + forma (“form”).
Etymology from Wiktionary, CC BY-SA 4.0.