[1] : The Collaborative International Dictionary of English v.0.48

laborious \labo"rious\, a. l. laboriosus, fr. labor labor:
   cf. f. laborieux.
   1. requiring labor, perseverance, or sacrifices; toilsome;
      tiresome.
      1913 webster

            dost thou love watchings, abstinence, or toil,
            laborious virtues all? learn these from cato.
                                                  --addison.
      1913 webster

   2. devoted to labor; diligent; industrious; as, a laborious
      mechanic.
      1913 webster -- labo"riously, adv. --
      labo"riousness, n.
      1913 webster
see also:
labo"riously labo"riousness 

[2] : WordNet (r) 2.0

laboriously
     adv : in a laborious manner; "their lives were spent in committee
           making decisions for others to execute on the basis of
           data laboriously gathered for them"

[3] : Moby Thesaurus II by Grady Ward, 1.0

34 moby thesaurus words for "laboriously":
   ardently, arduously, assiduously, bec et ongles, burdensomely,
   difficultly, diligently, effortfully, energetically, fervently,
   hammer and tongs, hard, hardly, heart and soul, indefatigably,
   industriously, manfully, onerously, operosely, painfully,
   relentlessly, sedulously, strenuously, the hard way, tirelessly,
   toilsomely, tooth and nail, unsparingly, vehemently, with a will,
   with difficulty, with effort, with much ado, zealously

Laboriously >> L Words
Laboriously, definition of term: Laboriously
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