Re‐tard″ (?), v. t. [imp. & p. p.Retarded; p. pr. & vb. n.Retarding.] [L. retardare, retardatum; pref. re- re- + tardare to make slow, to delay, fr. tardus slow: cf. F. retarder. See Tardy.] 1. 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.
2. To put off; to postpone; as, to retard the attacks of old age; to retard a rupture between nations.
Syn. — To impede; hinder; obstruct; detain; delay; procrastinate; postpone; defer.