If sea horse are called as poor swimmers than why they named horse?

Seahorses are not called poor swimmers. They are actually quite good at swimming and can move quickly through the water. They have a unique body shape and fins that allow them to maneuver easily and change direction quickly. They also have a long tail that they can use to anchor themselves to objects in the water.

They are called "horses" because of their head shape, which resembles that of a horse.