forsweal means to burn up. Lexicurio rates it Rare gem — a strength score of 84 out of 100.
Why “forsweal” is a great word
FORSWEAL — [Verb] To burn up completely. From Middle English forswelen, forswælen, from Old English forswǣlan, meaning 'to burn, burn up, inflame, consume', equivalent to the intensive prefix for- + sweal (to burn). Unlike "singe," which merely scorches a surface, or "incinerate," which denotes a controlled, industrial reduction, to forsweal is the older, more absolute consumption—the fire that asks for everything. It is the candlewick guttering into a final bead of smoke, the last log crumbling to embers and then to air, the pyre that does its duty until only memory remains; a quiet, total victory of flame over form.
Etymology
From Middle English forswelen, forswælen, from Old English forswǣlan (“to burn, burn up, inflame, consume”), equivalent to for- + sweal.