What is the X in X-mas?
Old English hæft "handle," related to hæft "fetter," from Proto-Germanic *haftjom (cf. Old Saxon haft "captured;" Dutch hecht, Old High German hefti, German Heft "handle;" German Haft "arrest"), from PIE *kap- "to grasp" (see capable). To haven other haeftes in hand "have other hafts in hand" was a 14c.-15c. way of saying "have other business to attend to."
a handle as of a dagger (Judg. 3:22).