ˈsərd.ərˌbrand noun
( -s )
Etymology: Icelandic surtarbrandr jet, surturbrand, from Surtr, giant fire demon in Scandinavian legend (akin to Old Norse svartr black) + Icelandic brandr firebrand, from Old Norse — more at swart , brand
: a variety of lignite in Iceland and the Faeroes occurring in seams between beds of volcanic rock