say it: ri-TAHRD
retard is a verb and noun meaning "cause to move more slowly or operate at a slower rate". It carries 5 recorded senses.
cause to move more slowly or operate at a slower rate
“This drug will retard your heart rate”
be delayed
slow the growth or development of
“The brain damage will retard the child's language development”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for retard come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.