n 1  :  a program or plan that indicates the sequence of each step or procedure <reinforcement s used in conditioning experiments>  : esp  :  REGIMEN <penicillin s for treating syphilis>   2  usu cap  :  an official list of drugs that are subject to the same legal controls and restrictions - usu. used with a Roman numeral from I to V indicating decreasing potential for abuse or addiction <the Drug Enforcement Administration classifies heroin as a I drug while the tranquilizer chlordiazepoxide is on IV> 
, vt, sched*uled  sched*ul*ing  :  to place in a schedule <methadone and phenobarbital are scheduled substances>  .
 
  Canad also  Brit usu   
 
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