The story
- Proto-Indo-European*né
- Proto-Indo-European*n̥-
- Proto-Italic*n̥-
- Latinin-
- Latinpaveō
- Proto-Indo-European*dʰeh₁-
- Latinpavidus
- Latinimpavidus
- English todayimpavid
From Latin impavidus, itself from im- (“not”) + pavidus (“fearful”).
Etymology from Wiktionary, CC BY-SA 4.0.