retard
1 of 2verb
re·tard ri-ˈtärd 
retarded; retarding; retards
transitive verb
: to delay or impede the development or progress of : to slow up especially by preventing or hindering advance or accomplishment
chemicals to retard the spread of fire
intransitive verb
: to become delayed : to undergo retardation
retarder noun
retard
2 of 2noun
re·tard
plural retards
1
ri-ˈtärd : a holding back or slowing down : retardation
: a holding back or slowing down : retardation 2
ˈrē-ˌtärd offensive : a person affected with intellectual disability
offensive : a person affected with intellectual disability 3
ˈrē-ˌtärd informal + offensive : a foolish or stupid person
informal + offensive : a foolish or stupid person 
Synonyms
Verb
- brake
- decelerate
- slacken
- slow
See all Synonyms & Antonyms 
Example Sentences
Verb The chemical will retard the spread of fire. The problems have retarded the progress of the program.
Word History
Etymology
Verb
Middle English, from Anglo-French or Latin; Anglo-French retarder, from Latin retardare, from re- + tardus slow
First Known Use
Verb
15th century, in the meaning defined at transitive sense
Noun
1781, in the meaning defined at sense 1
Kids Definition
retard
verb
re·tard ri-ˈtärd
retarded; retarding
: to slow down : delay
Bad weather retarded our progress.
Medical Definition
retard
transitive verb
re·tard ri-ˈtärd
: to slow up especially by preventing or hindering advance or development
retard spoilage
retard hair loss
retarding
verb
as in slowing
to cause to move or proceed at a less rapid pace an herbicide to retard the growth of weeds Synonyms & Similar Words
Relevance
- slowing
- braking
- inhibiting
- hindering
- impeding
- decelerating
- slackening
- restraining
- stopping
- halting
- obstructing
- hampering
- curbing
- thwarting
- handicapping
- checking
- encumbering
- constraining
- sabotaging
- hobbling
- reining
- arresting
- foiling
- tying up
- holding back
- setting back
- bottlenecking
- frustrating
- baffling
- tieing up
- holding up
Antonyms & Near Antonyms
- accelerating
- hastening
- rushing
- pushing
- driving
- encouraging
- propelling
- quickening
- urging
- aiding
- advancing
- speeding (up)
- stirring
- facilitating
- stepping up
- furthering
- helping
- expediting
- hurrying
- spurring
- forwarding
- easing
- goading
- dispatching
- national debt
- National Democratic
- national economy
- national emergency
- national ensign
- national flag
- national flag blue
- national forest
- national guard
- national guards
- national guardsman
- national holiday
- national income
- National Insurance
- national interest
- national meridian
- national mission
- national monument
- national park
- national product
- National Republican
- national road
- national salute
- national school
- national school-bus chrome