Source : Webster's Revised Unabridged Dictionary (1913)

Stupendous \Stu*pen"dous\, a. [L. stupendus astonishing, p.
   future pass. of stupere to be astonished at. Cf. {Stupid}.]
   Astonishing; wonderful; amazing; especially, astonishing in
   magnitude or elevation; as, a stupendous pile. ``A stupendous
   sum.'' --Macaulay.

         All are but parts of one stupendous whole. --Pope.
   -- {Stu*pen"dous*ly}, adv. -- {Stu*pen"dous*ness}, n.

Source : WordNet®

stupendous
     adj : so great in size or force or extent as to elicit awe;
           "colossal crumbling ruins of an ancient temple"; "has a
           colossal nerve"; "a prodigious storm"; "a stupendous
           field of grass"; "stupendous demand" [syn: {colossal},
           {prodigious}]