The Collaborative International Dictionary of English v.0.48:

Styryl \Sty"ryl\, n. [Styrax + -yl.] (Chem.)
   A hypothetical radical found in certain derivatives of
   styrolene and cinnamic acid; -- called also cinnyl, or
   cinnamyl.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Cinnamyl \Cin"na*myl\, n. [Cinnamic + -yl.] (Chem.)
   The hypothetical radical, (C6H5.C2H2)2C, of cinnamic
   compounds. [Formerly written also cinnamule.]
   [1913 Webster]