(n)a monoamine neurotransmitter found in the brain and essential for the normal functioning of the central nervous system; as a drug (trade names Dopastat and Intropin) it is used to treat shock and hypotension, Syn.Dopastat, Intropin
The Collaborative International Dictionary of English (GCIDE) v.0.53Collaborative International Dictionary (GCIDE)
n. a foreign substance added to a material to alter its properties; -- a process used. e.g., in making semiconductors from pure silicon in the manufacture of semiconductor chips and integrated circuits. [ PJC ]