An object does not have a varying speed if its velocity is constant. A constant velocity implies that an object is moving in a straight line at an identical rate over time.
When an object has a constant velocity, it moves an equal distance in an equal direction over equal periods of time. Both speed and direction are unchanging when an object has constant velocity. It is, however, possible to have an item with constant speed change velocity. Speed is the magnitude of an object's velocity; an object can have constant speed but changing direction. According to Zona Land Education, an example of this is when a car goes around a curve at a constant speed; its velocity changes because its direction changes.