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

strenuous \stren"uous\, a. l. strenuus; cf. gr. ? strong,
   hard, rough, harsh.
   eagerly pressing or urgent; zealous; ardent; earnest; bold;
   valiant; intrepid; as, a strenuous advocate for national
   rights; a strenuous reformer; a strenuous defender of his
   country.
   1913 webster

         and spirit-stirring wine, that strenuous makes.
                                                  --chapman.
   1913 webster

         strenuous, continuous labor is pain.     --i. taylor.
   1913 webster -- stren"uously, adv. --
   stren"uousness, n.
   1913 webster
see also:
stren"uously stren"uousness 

[2] : WordNet (r) 2.0

strenuous
     adj 1: characterized by or performed with much energy or force;
            "strenuous exercise"
     2: taxing to the utmost; testing powers of endurance; "his
        final, straining burst of speed"; "a strenuous task";
        "your willingness after these six arduous days to remain
        here"- f.d.roosevelt syn: arduous, straining
see also:
arduous straining 

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

39 moby thesaurus words for "strenuous":
   herculean, active, arduous, breathless, burdensome, demanding,
   determined, difficult, dogged, dynamic, eager, earnest, effortful,
   energetic, enthusiastic, exhausting, hard, indefatigable, intense,
   laborious, lusty, mean, operose, persistent, pertinacious,
   red-blooded, resolute, sincere, taxing, tenacious, tireless,
   tiring, toilsome, tough, uphill, vigorous, vital, wicked,
   zealous

Strenuous >> S Words
Strenuous, definition of term: Strenuous
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