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

terrible \ter"rible\, a. f., fr. l. terribilis, fr. terrere to
   frighten. see terror.
   1. adapted or likely to excite terror, awe, or dread;
      dreadful; formidable.
      1913 webster

            prudent in peace, and terrible in war. --prior.
      1913 webster

            thou shalt not be affrighted at them; for the lord
            thy god is among you, a mighty god and terrible.
                                                  --deut. vii.
                                                  21.
      1913 webster

   2. excessive; extreme; severe. colloq.
      1913 webster

            the terrible coldness of the season.  --clarendon.
      1913 webster

   syn: terrific; fearful; frightful; formidable; dreadful;
        horrible; shocking; awful.
        1913 webster -- ter"ribleness, n. -- ter"ribly,
        adv.
        1913 webster
see also:
terror ter"ribleness ter"ribly 

[2] : WordNet (r) 2.0

terrible
     adj 1: causing fear or dread or terror; "the awful war"; "an awful
            risk"; "dire news"; "a career or vengeance so direful
            that london was shocked"; "the dread presence of the
            headmaster"; "polio is no longer the dreaded disease
            it once was"; "a dreadful storm"; "a fearful howling";
            "horrendous explosions shook the city"; "a terrible
            curse" syn: awful, dire, direful, dreada, dreaded,
             dreadful, fearful, fearsome, frightening, horrendous,
             horrific
     2: exceptionally bad or displeasing; "atrocious taste";
        "abominable workmanship"; "an awful voice"; "dreadful
        manners"; "a painful performance"; "terrible handwriting";
        "an unspeakable odor came sweeping into the room" syn: atrocious,
         abominable, awful, dreadful, painful, unspeakable
     3: intensely or extremely bad or unpleasant in degree or
        quality; "severe pain"; "a severe case of flu"; "a
        terrible cough"; "under wicked fire from the enemy's
        guns"; "a wicked cough" syn: severe, wicked
     4: extremely distressing; "fearful slum conditions"; "a
        frightful mistake"; "suffered terrible thirst" syn: fearful,
         frightful
see also:
awful dire direful dreada dreaded dreadful 
fearful fearsome frightening horrendous horrific 
atrocious abominable painful unspeakable severe 
wicked frightful 

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

188 moby thesaurus words for "terrible":
   aberrant, abnormal, abominable, acute, alarming, appalling,
   arduous, arrant, ashamed, astounding, atrocious, awe-inspiring,
   awesome, awful, bad, baneful, base, beastly, beneath contempt,
   blameworthy, brutal, concentrated, conscience-stricken,
   contemptible, contrite, criminal, deadly, delinquent, deplorable,
   desperate, despicable, detestable, deviant, difficult, dire,
   direful, disagreeable, disgraceful, disgusting, distressed,
   distressing, dread, dreaded, dreadful, egregious, enormous, evil,
   exquisite, fearful, fearsome, fell, fetid, fierce, filthy,
   flagrant, forbidding, formidable, foul, frightening, frightful,
   fulsome, furious, ghastly, ghoulish, gory, grave, grievous, grim,
   grisly, gross, grotesque, gruesome, guilty, hardly the thing,
   harrowing, hateful, heavy, heinous, hideous, horrendous, horrible,
   horrid, horrific, horrifying, howling, ignominious, illegal,
   improper, inappropriate, incorrect, indecorous, infamous,
   intolerable, joyless, laborious, lamentable, loathsome, lousy,
   macabre, mephitic, miserable, monstrous, morbid, nasty, nauseating,
   nauseous, nefarious, noisome, not done, not the thing, notorious,
   noxious, obnoxious, odious, off-base, off-color, offensive,
   out-of-line, outrageous, pitiable, pitiful, rank, redoubtable,
   regretful, regrettable, remorseful, repelling, reprehensible,
   repugnant, repulsive, revolting, rotten, rousing, rueful,
   sacrilegious, sad, savage, scandalous, schlock, schrecklich,
   scurvy, serious, severe, shabby, shameful, shameless, shocking,
   shoddy, sinful, sordid, sorry, squalid, strenuous, terrible,
   terrific, terrifying, thumping, toilsome, too bad, tough, tragic,
   tremendous, unbearable, unclean, undue, unfit, unfitting,
   unfortunate, unhappy, unlawful, unpleasant, unrighteous, unseemly,
   unspeakable, unsuitable, vehement, vicious, vile, villainous,
   violent, whacking, wicked, woeful, worst, worthless, wretched,
   wrong, wrongful

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