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

terrific \terrif"ic\, a. l. terrificus; fr. terrere to
   frighten + facere to make. see terror, and fact.
   causing terror; adapted to excite great fear or dread;
   terrible; as, a terrific form; a terrific sight.
   1913 webster
see also:
terror fact 

[2] : WordNet (r) 2.0

terrific
     adj 1: very great or intense; "a terrific noise"; "a terrific
            thunderstorm storm"; "fought a terrific battle"
     2: extraordinarily good; used especially as intensifiers; "a
        fantastic trip to the orient"; "the film was fantastic";
        "a howling success"; "a marvelous collection of rare
        books"; "had a rattling conversation about politics"; "a
        tremendous achievement" syn: fantastic, howlinga, marvelous,
         marvellous, rattlinga, tremendous, wonderful, wondrous
     3: causing extreme terror; "a terrifying wail" syn: terrifying
see also:
fantastic howlinga marvelous marvellous rattlinga tremendous 
wonderful wondrous terrifying 

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

82 moby thesaurus words for "terrific":
   ace, agitating, appalling, astounding, awe-inspiring, awesome,
   awful, breathtaking, deadly, dire, direful, disquieting, divine,
   dread, dreaded, dreadful, excellent, exceptional, exquisite,
   extraordinary, fabulous, fantastic, fearful, fell, first-class,
   formidable, frightful, ghastly, ghoulish, gilt-edged, glorious,
   golden, great, grim, grisly, groovy, gruesome, heavenly, hideous,
   horrendous, horrible, horrid, horrific, horrifying, hot, howling,
   immense, incredible, keen, macabre, magnificent, marvelous,
   mind-boggling, morbid, outstanding, rattling, redoubtable, rousing,
   schrecklich, screaming, sensational, shocking, smashing, splendid,
   splendiferous, sterling, stupendous, super, superb, supereminent,
   superexcellent, superfine, superior, swell, terrible, terrorizing,
   thumping, tremendous, unbelievable, upsetting, whacking,
   wonderful

Terrific >> T Words
Terrific, definition of term: Terrific
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