Retard

To keep delaying; to continue to hinder; to prevent from progress; to render more slow in progress; to impede; to hinder; as, to retard the march of an army; to retard the motion of a ship; -- opposed to accelerate.

To put off; to postpone; as, to retard the attacks of old age; to retard a rupture between nations.

To stay back.

Retardation; delay.

lose velocity; move more slowly; "The car decelerated"