packpackpackspackedpacking2verb (packs, packing, packed)1to put things into a bag or suitcase before you go somewhere: Have you packed your suitcase? Don't forget to pack your toothbrush.2to put things into a box, bag, etc.: Pack all these books into boxes.oppositeunpackpack up1to stop doing something: At two o'clock we packed up and went home.2(British, informal) If a machine packs up, it stops working.packpackpacks1noun1a set of things: I bought a pack of five exercise books.an information pack2 (British) (Americandeck)a set of 52 cards for playing games3a group of wild dogs or similar animals: a pack of wolves3 American English for packet: a pack of cigarettes