Source : Webster's Revised Unabridged Dictionary (1913)

Propenyl \Pro"pe*nyl\, n. [Propene + -yl.] (Chem.)
   A hypothetical hydrocarbon radical, {C3H5}, isomeric with
   allyl and glyceryl, and regarded as the essential residue of
   glycerin. Cf. {Allyl}, and {Glyceryl}.

Allyl \Al"lyl\, n. [L. allium garlic + -yl.] (Chem.)
   An organic radical, {C3H5}, existing especially in oils of
   garlic and mustard.

Glyceryl \Glyc"er*yl\, n. [Glycerin + -yl.] (Chem.)
   A compound radical, {C3H5}, regarded as the essential radical
   of glycerin. It is metameric with allyl. Called also
   {propenyl}.