/neuh lok"sohn, nal"euhk sohn'/ , n. Pharm.
a narcotic analgesic antagonist, C 19 H 21 NO 4 , used in the reversal of acute narcotic analgesic respiratory depression.
[ 1960-65; by shortening and rearrangement of dihydroxy-, morphinan-, and -one, components of its chemical name ]