The story
- Proto-Indo-European*né
- Proto-Indo-European*n̥-
- Proto-Germanic*un-
- Proto-West Germanic*un-
- Old Englishun-
- Middle Englishun-
- Englishun-
- Proto-Indo-European*dwóh₁
- Proto-Indo-European*trísinflu.
- Proto-Indo-European*d(w)is-
- Proto-Italic*dis-
- Latindis-
- Old Frenchdes-
- Proto-Indo-European*werb-
- Proto-Germanic*wrappan-
- Vulgar Latin*vlopp-
- Old Frenchveloper
- Middle Frenchdesveloper
- Frenchdévelopper
- Englishdevelop
- Englishdeveloped
- Englishundeveloped
- Proto-Indo-European*leyg-
- Proto-Germanic*līką
- English todayundevelopedly
From undeveloped + -ly.
Etymology from Wiktionary, CC BY-SA 4.0.