The Collaborative International Dictionary of English v.0.48:

Elbowroom \El"bow*room`\, n.
   Room to extend the elbows on each side; ample room for motion
   or action; free scope. "My soul hath elbowroom." --Shak.
   [1913 Webster]

         Then came a stretch of grass and a little more
         elbowroom.                               --W. G.
                                                  Norris.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "elbowroom":
   air space, ample scope, blank check, carte blanche, clearance,
   field, free course, free hand, free play, free scope, full scope,
   full swing, headroom, latitude, leeway, long rope,
   maneuvering space, margin, no holds barred, open space, play,
   range, room, room to spare, rope, scope, sea room, space,
   spare room, swing, tolerance, way, wide berth