From Old French 'furnir' (to provide), from Frankish *frumjan (to carry out) — a Germanic word that returned through French.
To provide a house or room with furniture and fittings; to supply someone with something needed or desired.
From Old French 'furniss-' (stem of 'furnir,' to provide, to equip, to accomplish), from Frankish *frumjan (to provide, to carry out), from Proto-Germanic *frumjaną (to further, to promote), from *frumô (benefit, advancement). The word is Germanic in ultimate origin but entered English through French. The furniture-specific sense developed in the 16th century