Definify.com
Webster 1913 Edition
Inertia
2.
Inertness; indisposition to motion, exertion, or action; lack of energy; sluggishness.
Men . . . have immense irresolution and
inertia
. Carlyle.
3.
(Med.)
Lack of activity; sluggishness; – said especially of the uterus, when, in labor, its contractions have nearly or wholly ceased.