1. Relatively slow in mental, emotional or physical development
   "providing a secure and sometimes happy life for the retarded";
   - mentally retarded

1. People with intellectual or developmental disabilities
   "he started a school for the retarded";
   - developmentally challenged

1. Cause to move more slowly or operate at a slower rate
   "This drug will retard your heart rate"
    
2. Slow the growth or development of
   "The brain damage will retard the child's language development";
   - check, delay
    
3. Lose velocity; move more slowly
   "The spacecraft retarded as it entered the atmosphere";
   - decelerate, slow, slow down, slow up
    
4. Be delayed
   "The project retarded due to unforeseen circumstances"

See also: backward, cretinous, dim-witted [informal], dull-witted [archaic], feebleminded, half-witted, imbecilic [archaic], moronic [archaic, informal], simple, simple-minded, slow-witted, stupid, unintelligent

Type of: alter, be, change, come down, decelerate, decrease, dent, diminish, exist, fall, go down, lessen, modify, people, sink, slow down

Antonym: precocious

Encyclopedia: Retarded