The Collaborative International Dictionary of English v.0.48:

Roin \Roin\, n. [F. rogne. See Roynish.]
   A scab; a scurf, or scurfy spot. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Roin \Roin\, v. t.
   See Royne. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Royne \Royne\ (roin), v. t. [F. rogner, OF. rooignier, to clip,
   pare, scare, fr. L. rotundus round See Rotund.]
   To bite; to gnaw. [Written also roin.] [Obs.] --Spenser.
   [1913 Webster]