Definition of pack:
(n) :
a bundle made up and prepared to be carried; especially, a bundle to be carried on the back; a load for an animal; a bale, as of goods; a number or quantity equal to the contents of a pack; hence, a multitude; a burden
(v) :
to make a pack of; to arrange closely and securely in a pack; hence, to place and arrange compactly as in a pack; to press into close order or narrow compass; as to pack goods in a box; to pack fish; to fill in the manner of a pack, that is, compactly and securely, as for transportation; hence, to fill closely or to repletion; to stow away within; to cause to be full; to crowd into; as, to pack a trunk; the play, or the audience, packs the theater