zbijati

1. (+ šale) to crack jokes
   Stalno zbija šale na račun svog šefa. — He keeps cracking jokes about his boss.
2. to crowd together; to cram
   Putnike zbijaju u autobus kao sardine. — They cram passengers into the bus like sardines.
3. (zbijati se) to huddle together
   Ovce se zbijaju jedna uz drugu zbog hladnoće. — The sheep huddle together because of the cold.
4. to compress; to pack down
   Radnici zbijaju zemlju valjkom. — The workers are packing down the soil with a roller.

A very frequent combination is zbijati šale (na nečiji račun), to joke about someone.