What is the meaning of Spanker?

Someone who spanks.

An instrument used to give someone a spanking or spank, such as a paddle.

A fore-and-aft gaff-rigged sail on the aft-most mast of a square-rigged vessel.

A musician who plays his instrument well.

A small coin.

One who takes long, quick strides in walking.

A swift horse.

Something very large, or larger than usual; a whopper.

Something splendid; a fine example of its kind.

Source: wiktionary.org