retardation

retardation — noun

1. the condition of developing or happening at a slower rate than is normal or expe

1.nounC1
Definition

the condition of developing or happening at a slower rate than is normal or expected

Example

Hari's construction project suffered a retardation when the building materials did not arrive on time.

Early treatment helped reduce the retardation of Layla's physical development caused by the rare condition.

pattern: retardation + of + noun phrase

Common collocations
  • growth retardation
  • economic retardation
  • developmental retardation
  • retardation in development
  • retardation of progress
Synonyms
  • delay

    broader term for any instance of being late or postponed; less formal than 'retardation'

  • slowdown

    focuses on a reduction in speed or rate, often used in economic or production contexts

  • deceleration

    more technical, often used in physics or transport contexts to describe a reduction in velocity

Antonyms
  • acceleration

    increase in speed or rate of progress

  • advancement

    forward movement or improvement, the opposite of being held back

Grammar Patterns

retardation + in + noun phrase

retardation + of + noun phrase

Usage Note

Often appears in compound phrases such as "growth retardation" or "economic retardation." Not used for short, everyday delays — for those, use "delay."

Common Mistakes

The train's retardation was due to heavy snow.
The train's delay was due to heavy snow.
'retardation' refers to a more lasting or systemic slowing of development or progress, not a short, everyday delay.

2. an outdated medical label for a condition where a person has much lower than usu

2.nounC1
Definition

an outdated medical label for a condition where a person has much lower than usual intellectual ability, now called an intellectual disability

Example

The 1970s medical file used the word retardation for a condition now called intellectual disability.

historical clinical term contrasted with modern term

Mayumi found the word retardation in old medical reports from Taiwan and Japan from the 1960s.

Common collocations
  • mental retardation (historical)
  • diagnosed with retardation (dated)
  • retardation center (historical facility name)
Synonyms
  • intellectual disability

    the modern, respectful term for this condition; preferred in all current clinical and educational contexts

  • cognitive impairment

    broader term that includes various types and degrees of reduced cognitive function

  • developmental disability

    umbrella term covering intellectual disabilities and other conditions that begin during development

Grammar Patterns

mental retardation (historical compound)

retardation as a standalone clinical label

Usage Note

This sense is now considered outdated and potentially offensive. In modern professional and educational settings, use 'intellectual disability' instead. The term was commonly used in medical records and legislation from the early 1900s through the late 20th century.

Common Mistakes

The clinic provides services for people with retardation.
The clinic provides services for people with intellectual disabilities.
'retardation' is outdated and potentially offensive; use 'intellectual disability' for respectful, modern usage.

Word family

  • retard
    verbC1
  • retarded
    adjectiveC1
  • retardant
    nounC1
  • retarder
    nounC2

Synonym discussion

Sense: noun/1

While 'retardation,' 'delay,' 'slowdown,' 'stagnation,' and 'deceleration' all refer to a reduction in speed or progress, they differ in scope and context. 'Delay' is the most general term and applies to any instance of being late or postponed, from a five-minute train hold-up to a project setback. 'Slowdown' describes a measurable reduction in rate or activity, common in economic or production reports. 'Stagnation' goes further, implying a complete lack of movement or growth over a prolonged period, as in a stagnant economy or career. 'Deceleration' is the most technical, usually referring to a calculated reduction in velocity in physics, engineering, or transport contexts. 'Retardation' sits closest to 'slowdown' but is more formal and often suggests a systemic or developmental lag rather than a temporary dip. For example, economists discuss an 'economic slowdown' in quarterly data but 'economic retardation' when describing long-term structural underperformance.

delay ↗slowdownstagnationdeceleration

Common collocations

Nouns

Phrases

  • rate of retardation
  • degree of retardation
  • cause of retardation

Prepositions

Etymology

LatinFrenchEnglish

The word 'retardation' comes from the Latin verb 'retardare', meaning 'to make slow' or 'to delay'. This verb is formed from the prefix 're-' (back) and 'tardare' (to make slow), which itself comes from the adjective 'tardus' (slow). The word entered English in the 15th century from French 'retardation'. For most of its history it was used for any kind of slowing or delay — in growth, progress, or movement. In the early 20th century, it took on a specific clinical meaning in psychology and medicine, referring to intellectual disability. That clinical use has since been replaced by more respectful terminology, though the word remains in use for general and technical descriptions of slowness.