The story
- Proto-Germanic · derived from*galmaz“echo”
- English todayBergelmir
From the Old Norse name; the second element means "yeller," from the verb *gallmr, from Proto-Germanic *galmaz (“echo”). The first element has been variously interpreted as berg (“mountain”), berr (“bare”), and a variant of bjǫrn (“bear”).
Etymology from Wiktionary, CC BY-SA 4.0.