Source : Webster's Revised Unabridged Dictionary (1913)

Labor \La"bor\, v. i. [imp. & p. p. {Labored}; p. pr. & vb. n.
   {Laboring}.] [OE. labouren, F. labourer, L. laborare. See
   {Labor}, n.] [Written also {labour}.]
   1. To exert muscular strength; to exert one's strength with
      painful effort, particularly in servile occupations; to
      work; to toil.

            Adam, well may we labor still to dress This garden.
                                                  --Milton.

   2. To exert one's powers of mind in the prosecution of any
      design; to strive; to take pains.

   3. To be oppressed with difficulties or disease; to do one's
      work under conditions which make it especially hard,
      wearisome; to move slowly, as against opposition, or under
      a burden; to be burdened; -- often with under, and
      formerly with of.

            The stone that labors up the hill.    --Granville.

            The line too labors,and the words move slow. --Pope.

            To cure the disorder under which he labored. --Sir
                                                  W. Scott.

            Come unto me, all ye that labor and are heavy laden,
            and I will give you rest.             --Matt. xi. 28

   4. To be in travail; to suffer the pangs of childbirth.

   5. (Naut.) To pitch or roll heavily, as a ship in a turbulent
      sea. -- Totten.

Laboring \La"bor*ing\, a.
   1. That labors; performing labor; esp., performing coarse,
      heavy work, not requiring skill also, set apart for labor;
      as, laboring days.

            The sleep of a laboring man is sweet. --eccl. v. 12.

   2. Suffering pain or grief. --Pope.

   {Laboring oar}, the oar which requires most strength and
      exertion; often used figuratively; as, to have, or pull,
      the laboring oar in some difficult undertaking.

Source : WordNet®

laboring
     adj : doing arduous or unpleasant work; "drudging peasants"; "the
           bent backs of laboring slaves picking cotton"; "toiling
           coal miners in the black deeps" [syn: {drudging}, {labouring},
            {toiling}]