re⋅tard  /rɪˈtɑrd, for 1–3, 5; ˈritɑrd for 4/ Show Spelled Pronunciation [ri-tahrd, for 1–3, 5; ree-tahrd for 4] Show IPA
–verb (used with object) 1. to make slow; delay the development or progress of (an action, process, etc.); hinder or impede.

–verb (used without object) 2. to be delayed.

–noun 3. a slowing down, diminution, or hindrance, as in a machine.
4. Slang: Disparaging. a. a mentally retarded person.
b. a person who is stupid, obtuse, or ineffective in some way: a hopeless social retard.

5. Automotive, Machinery. an adjustment made in the setting of the distributor of an internal-combustion engine so that the spark for ignition in each cylinder is generated later in the cycle.

Compare advance.


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Origin:
1480–90; < L retardāre to delay, protract, equiv. to re- re- + tardāre to loiter, be slow, deriv. of tardus slow; see tardy

Related forms:

re⋅tard⋅ing⋅ly, adverb


Synonyms:
1. obstruct, check.


Antonyms:
1. accelerate.

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2010.
Cite This Source |Link To retarded
re·tard 1 (rĭ-tärd')
v. re·tard·ed, re·tard·ing, re·tards

v. tr.
To cause to move or proceed slowly; delay or impede.
v. intr.
To be delayed.
n.
A slowing down or hindering of progress; a delay.

Music A slackening of tempo.


[Middle English retarden, from Old French retarder, from Latin retardāre : re-, re- + tardāre, to delay (from tardus, slow).]
re·tard'er n.
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