1. put together in a pack, make a pack or package of2. colloq. give up an enterprise, stop what one is doing; surrender; die; (of a machine etc.) cease working, break down
If a machine or a part of the body packs up, it stops working. In the end it was his stomach and lungs that packed up
If you pack up or if you pack up your things, you put your possessions or the things you have been using in a case or bag, because you are leaving. They packed up and went home He began packing up his things