Source : Webster's Revised Unabridged Dictionary (1913)

Strop \Strop\, v. t. [imp. & p. p. {Stropped}; p. pr. & vb. n.
   {Stropping}.]
   To draw over, or rub upon, a strop with a view to sharpen;
   as, to strop a razor.

Source : WordNet®

strop
     n : a leather strap used to sharpen razors
     [also: {stropping}, {stropped}]

strop
     v : sharpen on a strop; "strop razors"
     [also: {stropping}, {stropped}]

stropped
     See {strop}