👉 Unrelativistic is a concept in physics that refers to objects that are considered to be motionless relative to an observer at rest. It is often used in the context of relativistic effects such as time dilation and length contraction. The term "unrelativistic" means that these effects do not depend on the relative motion between the object and the observer, which is a fundamental principle in physics. Unrelativistic objects are said to have "zero velocity," meaning that they do not move