diphenhydramine

 
Pronunciation: /ˌdʌɪfɛnˈhʌɪdrəmiːn/

noun

[mass noun] Medicine
  • an antihistamine compound used for the symptomatic relief of allergies.
    • A synthetic amine, usually used as a hydrochloride salt; chemical formula: C17H21NO

Origin:

1940s: from diphen- (denoting the presence of two phenyl groups) + hydr- + amine