Glow
Old English glōwan, of Germanic origin; related to Dutch gloeien and German glühen .
wiktionary
From Middle English glowen, from Old English glōwan, from Proto-Germanic *glōaną, from Proto-Indo-European *ǵʰel-. Cognate with Saterland Frisian gloie, glöie, gluuje, West Frisian gloeie, Dutch gloeien, German glühen, Danish and Norwegian glo, Icelandic glóa. See also glass.
etymonline
glow (v.)
Old English glowan "to glow, shine as if red-hot," from Proto-Germanic *glo- (source also of Old Saxon gloian, Old Frisian gled "glow, blaze," Old Norse gloa, Old High German gluoen, German glühen "to glow, glitter, shine"), from PIE root *ghel- (2) "to shine," with derivatives referring to bright materials and gold. Figuratively from late 14c. Related: Glowed; glowing. Swedish dialectal and Danish glo also have the extended sense "stare, gaze upon," which is found in Middle English.
glow (n.)
mid-15c., "glowing heat," from glow (v.). Meaning "a flush of radiant feeling" is from 1793.