Definition

1. Verb:

   • To cause to move, proceed, or develop more slowly; to delay or impede: The primary meaning is to make something slower than it would otherwise be, either in physical motion or in progress/development.
   • To be delayed or slow down: To occur or progress at a slower than normal rate.

2. Noun:

   • A delay or slowing of progress: An instance of being slowed down.
   • A person with an intellectual disability (Offensive): This usage is now considered highly offensive and derogatory. It should be avoided.

Examples of Usage

• Verb:

  • Adding too much weight will retard the aircraft's acceleration.
  • Lack of sunlight can retard the growth of these plants.
  • The chemical is designed to retard the spread of flames.

• Noun (referring to a delay):

  • The project experienced a significant retard due to funding issues. (This noun form is technical/formal and less common in everyday speech.)

Advanced Usage

• Technical/Scientific Context: The verb is often used in technical fields (physics, engineering, chemistry, medicine) to describe the act of slowing a process.

  • The inhibitor retards the polymerization reaction.
  • This medication is used to retard the progression of the disease.

• Historical/Literary Context: The noun form meaning "delay" can be found in older or formal texts.

  • "Without retard, the army advanced."

Variants and Related Words

• Retardation (n): The act of retarding or the condition of being retarded; delay. In a medical/psychological context, it historically referred to intellectual disability (now largely replaced by terms like "intellectual and developmental disability" due to the offensive connotations of "retard").
• Retardant (n/adj): A substance that slows down a process (e.g., ). As an adjective: having the effect of slowing (e.g., ).
• Retarded (adj): Made slower or less developed. Its use to describe a person with an intellectual disability is now considered offensive and outdated.

CRITICAL NOTE ON OFFENSIVE USAGE: The use of "retard" as a noun or "retarded" as an adjective to describe a person is a severe slur. It is derogatory and hurtful. Appropriate, respectful language includes terms like "person with an intellectual disability" or "person with developmental delays."

Synonyms

• Verb: delay, slow (down), impede, hinder, decelerate, brake, hold back, set back.
• Noun (delay): delay, slowdown, deceleration, hindrance, impediment.

Antonyms

• Verb: accelerate, speed up, advance, promote, expedite, hasten.

Related Phrases/Idioms

• Fire retardant: A substance that slows or resists the spread of fire.
• Flame retardant: Similar to fire retardant, specifically inhibiting ignition or flame spread.
• Mental retardation (Outdated/Offensive): An outdated clinical term for intellectual disability. Its use is now widely discouraged in professional and social contexts.

Noun

1. a person of subnormal intelligence

Verb

1. lose velocity; move more slowly
   • The car decelerated
2. slow the growth or development of
   • The brain damage will retard the child's language development
3. be delayed
4. cause to move more slowly or operate at a slower rate
   • This drug will retard your heart rate