The best replacement for retardation is autism.

The best alternatives to retardation are rated as following:
★★★★★  autism
★★★  mental illness
★★★  intellectual disability
★★★  learning disability
★★  agitation
★  developmental delay
★  down syndrome
★  developmental disability
★  deceleration
  developmental disabilities
  cognitive impairment
  intellectual disabilities
  brain damage
  global developmental delay
  learning disabilities
  developmentally delayed
  downs syndrome
  learning disorder
  low functioning autism
  developmental delays
  borderline intellectual functioning
  learning disabled

Your alternative for retardation is not listed? Suggest!
Speaking about retardation, one probably shouldn't forget about psychosis.

Other search terms related to retardation and their ratings are:
★★★★★ psychosis
★★★★★ cerebral palsy
★★★★ autism
★★★ schizophrenia
★★ down syndrome
★ seizure disorder
microcephaly
muscular dystrophy
You have in mind a companion for retardation and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of retardation in all years. Click on graph for more.
retardation
autism
mental illness