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levorphanol tartrate

[lĕ-vôr′fə-nôl′]
n.
  1. An addictive drug used primarily as an analgesic with action similar to morphine.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.