dubiti

1. (of wood, stone) to hollow out; to carve
   Majstor polako dubi korito od jednog stabla. — The craftsman is slowly hollowing a trough out of a single trunk.
   Voda vekovima dubi stenu. — For centuries the water has been hollowing out the rock.
2. colloq. (of a person, usually waiting) to stand around; to stand for a long time
   Dubili smo ispred šaltera dva sata. — We stood around in front of the counter for two hours.
   Dubim na stanici već pola sata, a autobusa nema. — I've been standing at the stop for half an hour and there's no bus.

In the sense "to hollow out", the perfective is izdubiti.