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

vehement \ve"hement\, a. l. vehemens, the first part of which
   is perhaps akin to vehere to carry, and the second mens mind:
   cf. f. v'eh'ement. cf. vehicle, and mental.
   1913 webster
   1. acting with great force; furious; violent; impetuous;
      forcible; mighty; as, a vehement wind; a vehement torrent;
      a vehement fire or heat.
      1913 webster

   2. very ardent; very eager or urgent; very fervent;
      passionate; as, a vehement affection or passion. "vehement
      instigation." --shak. "vehement desire." --milton.
      1913 webster

   syn: furious; violent; raging; impetuous; passionate; ardent;
        eager; hot; fervid; burning.
        1913 webster
see also:
vehicle mental 

[2] : WordNet (r) 2.0

vehement
     adj 1: marked by extreme intensity of emotions or convictions;
            inclined to react violently; fervid; "fierce loyalty";
            "in a tearing rage"; "vehement dislike"; "violent
            passions" syn: fierce, tearing, violent, trigger-happy
     2: characterized by great force or energy; "vehement deluges of
        rain"; "vehement clapping"; "a vehement defense"
see also:
fierce tearing violent trigger-happy 

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

131 moby thesaurus words for "vehement":
   abandoned, acid, acidulous, acrid, acrimonious, acute, afire,
   ardent, assiduous, astringent, biting, bitter, burning, caustic,
   committed, concentrated, cutting, dedicated, delirious, desperate,
   devoted, devout, diligent, double-edged, drastic, earnest, edged,
   emphatic, energetic, enthusiastic, escharotic, excessive, exciting,
   exorbitant, exquisite, extravagant, extreme, faithful, fervent,
   fervid, fierce, fiery, flaming, forceful, frantic, furious,
   glowing, great, hard, hardworking, harsh, hearty, heated, hot,
   hot-blooded, hotheaded, immoderate, impassioned, impetuous,
   in earnest, incisive, indefatigable, industrious, intemperate,
   intense, intent, intent on, keen, laborious, lively, loyal,
   mordacious, mordant, never idle, on fire, outrageous, passionate,
   penetrating, perfervid, piercing, poignant, potent, powerful,
   pronounced, provoking, rabid, red-hot, relentless, resolute,
   rigorous, rough, scathing, sedulous, serious, severe, sharp,
   simmering, sincere, sleepless, spirited, splitting, stabbing,
   stimulating, stinging, stirring, stormy, strenuous, strident,
   stringent, tart, tempestuous, terrible, tireless, trenchant,
   unconscionable, unflagging, unremitting, unsleeping, unsparing,
   unwearied, urgent, venomous, vicious, violent, virulent, vitriolic,
   volcanic, warm, white-hot, wild, zealous

Vehement >> V Words
Vehement, definition of term: Vehement
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