An anagram is a word formed by rearranging all the letters of another word, using each letter exactly once. These words use every letter from "NSHTIGAW":
The melting of ice, snow, or other congealed matter; the resolution of ice, or the like, into the state of a fluid; liquefaction by heat of anything congealed by frost; also, a warmth of weather sufficient to melt that which is congealed.