motion that continues indefinitely without any external source of energy; impossible in practice because of friction
continuing forever or indefinitely
uninterrupted in time and indefinitely long continuing
the use of movements (especially of the hands) to communicate familiar or prearranged signals
a natural event that involves a change in the position or location of something
a change of position that does not entail a change of location
a state of change
show, express or direct through movement
the act of changing location from one place to another
