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diphenylhydantoin

American  
[dahy-fen-l-hahy-dan-toh-in, -feen-] / daɪˈfɛn l haɪˈdæn toʊ ɪn, -ˈfin- /

noun

Pharmacology.
  1. a white, slightly water-soluble powder, C 15 H 11 N 2 O 2 , used in the form of its sodium salt to prevent or arrest convulsions in epilepsy.


Etymology

Origin of diphenylhydantoin

First recorded in 1935–40; diphenyl + hydantoin