[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

laboriousness
     n : the quality of requiring extended effort syn: operoseness,
          toilsomeness
see also:
operoseness toilsomeness 

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