(1):

(v. i.) To rove or wander stealthily, esp. for prey, as a wild beast; hence, to prey; to plunder.

(2):

(v. t.) To collect by plunder; as, to prowl money.

(3):

(v. t.) To rove over, through, or about in a stealthy manner; esp., to search in, as for prey or booty.

(4):

(n.) The act of prowling.