If an object's velocity is constant, its motion is said to be uniform motion.

Here's why:

* Constant Velocity: This means the object is moving at a steady speed in a straight line. There is no change in either the speed or the direction of motion.

* Uniform Motion: This term specifically describes motion where both the speed and direction are constant.

Important Note: If the object's velocity is zero (not moving), it is still considered uniform motion because the velocity is constant.