The Collaborative International Dictionary of English v.0.48:

Orchard \Or"chard\, n. [AS. ortgeard, wyrtgeard, lit., wortyard,
   i. e., a yard for herbs; wyrt herb + geard yard. See Wort,
   Yard inclosure.]
   1. A garden. [Obs.]
      [1913 Webster]

   2. An inclosure containing fruit trees; also, the fruit
      trees, collectively; -- used especially of apples,
      peaches, pears, cherries, plums, or the like, less
      frequently of nutbearing trees and of sugar maple trees.
      [1913 Webster]

   Orchard grass (Bot.), a tall coarse grass (Dactylis
      glomerata), introduced into the United States from
      Europe. It grows usually in shady places, and is of value
      for forage and hay.

   Orchard house (Hort.), a glazed structure in which fruit
      trees are reared in pots.

   Orchard oriole (Zool.), a bright-colored American oriole
      (Icterus spurius), which frequents orchards. It is
      smaller and darker thah the Baltimore oriole.
      [1913 Webster]

WordNet (r) 3.0 (2006):

orchard grass
    n 1: widely grown stout Old World hay and pasture grass [syn:
         orchard grass, cocksfoot, cockspur, Dactylis
         glomerata]