the tendency of a body to resist acceleration; the tendency of a body at rest to remain at rest or of a body in motion to stay in motion in a straight line unless acted on by an outside force

• 惯性，物体抗拒加速的倾向；在没有外力作用的情况下，静止的物体保持静止状态的倾向，或运动着的物体保持匀速直线运动的倾向