Both are French importations of "valet" (the "t" being silent in modern French) or "varlet", Old French variants of "vaslet" "man's servant", originally "squire, young man", assumed to be from Gallo-Romance Vulgar Latin *"vassellittus" "young nobleman, squire, page", diminutive of Medieval Latin "vassallus", from "vassus" "servant", possibly cognate to an Old Celtic root "wasso-" "young man, squire" (source of Welsh "gwas" "youth, servant", Breton "goaz" "servant, vassal, man", Irish "foss" "servant").