What is the meaning of Fluke?

A lucky or improbable occurrence, with the implication that the occurrence could not be repeated.

To obtain a successful outcome by pure chance.

To fortuitously pot a ball in an unintended way.

A summer flounder (Paralichthys dentatus)

A trematode; a parasitic flatworm of the class Trematoda, related to tapeworms (class Cestoda).

Any of the triangular blades at the end of an anchor, designed to catch the ground.

Either of the two lobes of a whale's or similar creature's tail.

A metal hook on the head of certain staff weapons (such as a bill), made in various forms depending on function, whether used for grappling or to penetrate armour when swung at an opponent.

In general, a winglike formation on a central piece.

Waste cotton.

Source: wiktionary.org