Definitions:
a long-bodied chiefly marine fish with a cartilaginous skeleton, a prominent dorsal fin, and toothlike scales. most sharks are predatory, although the largest kinds feed on plankton, and some can grow to a large size.

a small se asian freshwater fish with a tail resembling that of a shark, popular in aquaria.

a light greyish-brown european moth, the male of which has pale silvery hindwings.

(typically of a man at a social gathering) be in active pursuit of a sexual partner

a person who unscrupulously exploits or swindles others

an expert in a specified field