The Collaborative International Dictionary of English v.0.48:

Mown \Mown\, p. p. & a.
   Cut down by mowing, as grass; deprived of grass by mowing;
   as, a mown field.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Mow \Mow\ (m[=o]), v. t. [imp. Mowed (m[=o]d); p. p. Mowed
   or Mown (m[=o]n); p. pr. & vb. n. Mowing.] [OE. mowen,
   mawen, AS. m[=a]wan; akin to D. maaijen, G. m[aum]hen, OHG.
   m[=a]jan, Dan. meie, L. metere to reap, mow, Gr. 'ama^n. Cf.
   Math, Mead a meadow, Meadow.]
   1. To cut down, as grass, with a scythe or machine.
      [1913 Webster]

   2. To cut the grass from; as, to mow a meadow.
      [1913 Webster]

   3. To cut down; to cause to fall in rows or masses, as in
      mowing grass; -- with down; as, a discharge of grapeshot
      mows down whole ranks of men.
      [1913 Webster]

WordNet (r) 3.0 (2006):

mown
    adj 1: (used of grass or vegetation) cut down with a hand
           implement or machine; "the smell of newly mown hay" [syn:
           mown, cut] [ant: uncut, unmown]