Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
ameliorate, counteract, mitigate, relieve (vv.)
All four words have to do, at least in part, with how to improve unsatisfactory conditions or situations. Ameliorate means “to make better, to improve”: The agency did what it could to ameliorate housing conditions. Counteract means “to use an equal and opposite force to prevent another force from dominating a situation”: These pills should counteract your indigestion. Mitigate and relieve both mean “to make less, to make easier, to reduce”: His kind words mitigated [relieved] her embarrassment somewhat. An important distinction is that you can counteract suffering, and you can mitigate or relieve it, but you cannot ameliorate suffering: that would “improve it,” which might well mean “increase it.” Compare MILITATE.
