(shärk) noun
One of a group of voracious elasmobranch fishes (order Selachii), mostly marine, of medium to large size, having a cartilaginous skeleton, lateral gill slits, and dun–colored bodies covered with placoid scales. Most species do not molest man; the great white shark (Carcharodon carcharias) is the man–eater frequenting warm seas.
—v.i. To fish for sharks. [Origin uncertain]
SHARKS
A. Great white shark (to 40 feet). B. Blue shark (to 15 feet). C. Hammerhead shark (to 15 feet).

(shärk) noun
1. A bold and dishonest person; a rapacious swindler.
2. Slang A person of exceptional skill or ability in some special line. Also shark′er.
—v.t. Archaic To obtain by unscrupulous or deceitful means.
—v.i. To live by trickery or deceit. [Prob. <G schurke scoundrel]