Source : Webster's Revised Unabridged Dictionary (1913)

Jackman \Jack"man\, n.; pl. {Jackmen}.
   1. One wearing a jack; a horse soldier; a retainer. See 3d
      {Jack}, n.

            Christie . . . the laird's chief jackman. --Sir W.
                                                  Scott.

   2. A cream cheese. [Obs.] --Sir T. Elyot.