Noah Webster
Retard
RET'ARD, verb transitive [Latin retardo; re and tardo, to delay, tardus, slow, late. See Target.]
1. To diminish the velocity of motion; to hinder; to render more slow in progress; as, to retard the march of an army; to retard the motion of a ship. The resistance of air retards the velocity of a cannon ball. It is opposed to accelerate.
2. To delay; to put off; to render more late; as, to retard the attacks of old age; to retard a rupture between nations. My visit was retarded by business.
RET'ARD, verb intransitive To stay back. [Not in use.]