1. (a.) Very ardent; very eager or urgent; very fervent; passionate; as, a vehement affection or passion\.

2. (a.) Acting with great force; furious; violent; impetuous; forcible; mighty; as, vehement wind; a vehement torrent; a vehement fire or heat.

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