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1. Cause to be more favourably inclined; gain the good will of
   "She managed to assuage the angry customer";
   - pacify, lenify, conciliate, appease, mollify, placate, gentle, gruntle
    
2. Satisfy (thirst)
   "The cold water assuaged his thirst";
   - quench, slake, allay
    
3. Provide physical relief, as from pain
   "This pill will assuage your headaches";
   - relieve, alleviate, palliate

Derived forms: assuaging, assuages, assuaged

Type of: ameliorate, amend, better, calm, calm down, conform to, fill, fit, fulfil [Brit, Cdn], fulfill [N. Amer], improve, lull, meet, meliorate, mend, quiet, quieten [Brit], satisfy, still, tranquilize [N. Amer], tranquillise [Brit], tranquillize