liege (adj.) Look up liege at Dictionary.com
c. 1300, of lords, "entitled to feudal allegiance and service," from Anglo-French lige (late 13c.), Old French lige "liege-lord," noun use of an adjective meaning "free, giving or receiving fidelity" (corresponding to Medieval Latin ligius, legius), a word of uncertain origin. Perhaps from Late Latin laeticus "cultivated by serfs," from laetus "serf," which probably is from Proto-Germanic *lethiga- "freed" (source also of Old English læt "half-freedman, serf;" Old High German laz, Old Frisian lethar "freedman;" Middle Dutch ledich "idle, unemployed"), from PIE root *le- (2) "let go, slacken" (see let (v.)). Or the Middle English word might be directly from Old High German leidig "free," on the notion of "free from obligation to service except as vassal to one lord," but this reverses the notion contained in the word.

From late 14c. of vassals, "bound to render feudal allegiance and service." The dual sense of the adjective reflects the reciprocal relationship it describes: protection in exchange for service. Hence, liege-man "a vassal sworn to the service and support of a lord, who in turn is obliged to protect him" (mid-14c.).
liege (n.) Look up liege at Dictionary.com
late 14c., "vassal of a feudal lord," also "a feudal sovereign, a liege-lord," probably from liege (adj.)) or from a noun use of the adjective in Old French or Anglo-French. A fully reciprocal relationship, so the adjective could apply to either party. Old French distinguished them as lige seignur "liege-lord" and home lige "liege-man."