to make slow; delay the development or progress of (an action, process, etc.); hinder or impede.

to be delayed.

a slowing down, diminution, or hindrance, as in a machine.

Slang

Disparaging

a mentally retarded person.

a person who is stupid, obtuse, or ineffective in some way

a hopeless social retard.

Automotive, Machinery . an adjustment made in the setting of the distributor of an internal-combustion engine so that the spark for ignition in each cylinder is generated later in the cycle.

verb

advance , help , push

verb

arrest , back off , baffle , balk , bog , bog down , brake , bring to screeching halt , check , choke , choke off , clog , close off , crimp , dawdle , decelerate , decrease , defer , delay , detain , down , encumber , falter , fetter , flag , hamper , handicap , hang up , hesitate , hold back , hold up , impede , lessen , let up , loaf , loiter , mire , poke , postpone , reduce , retardate , set back , shut down , shut off , slacken , slow down , slow up , stall , take down , lag , slow , hinder , inhibit , obstruct , prevent , stunt