nabijati

1. to cram; to stuff
   Uvek nabija previše stvari u kofer. — He always crams too much stuff into his suitcase.
2. (on a spit, skewer) to skewer; to impale
   Tata nabija meso na ražnjiće za roštilj. — Dad is skewering the meat for the barbecue.
3. colloq. (of a bill, debt, weight) to run up; to pile on
   Svaki mesec nabija račun za telefon. — Every month he runs up a huge phone bill.
   Preko zime je nabijala kilograme. — Over the winter she was piling on the kilos.
4. (stakes, nails) to drive in; to hammer in
   Radnici nabijaju kolce u zemlju duž ograde. — The workers are driving stakes into the ground along the fence.
5. (earth, gravel) to tamp down; to pack down
   Nabijamo zemlju oko stuba da bi čvrsto stajao. — We're tamping down the earth around the post so it stands firm.

The perfective is nabiti; nabijati nešto u nešto means to cram something into something.