Meaning : A decrease in rate of change.
Example :
The deceleration of the arms race.
Synonyms : deceleration, slowing
An increase in rate of change.
Modern science caused an acceleration of cultural change.Meaning : The extent to which something is delayed or held back.
Meaning : Lack of normal development of intellectual capacities.
Synonyms : backwardness, mental retardation, slowness, subnormality
Retardation meaning in Bengali (Bangla).