The Collaborative International Dictionary of English v.0.48:

Cow \Cow\, n.; pl. Cows (kouz); old pl. Kine (k[imac]n).
   [OE. cu, cou, AS. c[=u]; akin to D. koe, G. kuh, OHG. kuo,
   Icel. k[=y]r, Dan. & Sw. ko, L. bos ox, cow, Gr. boy^s, Skr.
   g[=o]. [root]223. Cf. Beef, Bovine, Bucolic, Butter,
   Nylghau.]
   [1913 Webster]
   1. The mature female of bovine animals.
      [1913 Webster]

   2. The female of certain large mammals, as whales, seals,
      etc.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

cows \cows\ n. pl. [pl. of cow.]
   domesticated bovine animals as a group regardless of sex or
   age; as, wait till the cows come home.

   Syn: cattle, kine, oxen, Bos taurus.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

cows
    n 1: domesticated bovine animals as a group regardless of sex or
         age; "so many head of cattle"; "wait till the cows come
         home"; "seven thin and ill-favored kine"- Bible; "a team of
         oxen" [syn: cattle, cows, kine, oxen, Bos taurus]