<p><strong>Noun</strong></p><ul><li>Inertness, especially with regard to effort, motion, action, and the like; inactivity; sluggishness.</li><li>Synonyms: laziness, inaction, torpor.</li><li>Physics: the property of matter by which it retains its state of rest or its velocity along a straight line so long as it is not acted upon by an external force.</li><li>An analogous property of a force: electric inertia.</li><li>Medicine/Medical: lack of activity, especially as applied to a uterus during childbirth when its contractions have decreased or stopped.</li></ul>