n. & v.
n. 1 a group of ships travelling together or under escort. 2 a supply of provisions etc. under escort. 3 a group of vehicles travelling on land together or under escort. 4 the act of travelling or moving in a group or under escort.
v.tr. 1 (of a warship) escort (a merchant or passenger vessel). 2 escort, esp. with armed force.
[ OF convoyer var. of conveier CONVEY ]