hilt (n.) Look up hilt at Dictionary.com
Old English hilt "hilt, handle of a sword or dagger," from Proto-Germanic *helt (cognates: Old Norse hjalt, Old High German helza "hilt," Old Saxon helta "oar handle"), of uncertain origin, possibly from PIE root *kel- (1) "to strike, cut" (see holt). Formerly also used in plural in same sense as singular. Up to the hilts "completely" is from 1670s.