Correct Answer: puddel

Solution : The fourth option is the correct answer.

The incorrectly spelt word is a puddle. 

The correct spelling is puddle, which refers to a small pool of liquid, especially rainwater, on the ground.

The meanings of the other options are as follows:

• Pillion refers to a cushioned seat for a passenger on a motorcycle or bicycle.
• Pioneer refers to a person who is among the first to explore or settle in a new area; a trailblazer.
• A pigeon refers to a bird of the family Columbidae, typically with a stout body and short legs.

Therefore, the correct answer is a puddle.