Etymology tree Proto-Indo-European *bʰel- Proto-Indo-European *-éh₁ti Proto-Indo-European *-yeti Proto-Indo-European *-éh₁yeti Proto-Indo-European *bʰl̥géh₁yeti Proto-Italic *folgēō Latin fulgeō Proto-Indo-European *dʰeh₁-der. Proto-Italic *-iðos Latin -idus Latin fulgidus English fulgid From Latin fulgidus, derived from fulgere. By surface analysis, Latin fulg(ere) + -id.