diphenhydramine
- n antihistamine (trade name Benadryl) used to treat allergic reactions involving the nasal passages (hay fever) and also to treat motion sickness
diphenylbutyl piperidine
- n a group of antipsychotic drugs used mainly in the treatment of schizophrenia
diphenylhydantoin
- n an anticonvulsant drug (trade name Dilantin) used to treat epilepsy and that is not a sedative
diphtheria
- n acute contagious infection caused by the bacterium Corynebacterium diphtheriae; marked by the formation of a false membrane in the throat and other air passages causing difficulty in breathing