What is the meaning of Holk?

A hollow cavity.

To dig out; make hollow; hollow out.

To dig; dig into; pierce; penetrate; investigate; poke.

To dig up; excavate.

hulk (large cargo ship)

hollow object; socket (like the shaft socket on a speartip)

a nest box, a birdhouse

a hulk, an old, decommissioned ship (used for storage or housing)

a pipe stuffed with cannabis, or more rarely a joint

Source: wiktionary.org