ameliorate

verb

ame·​lio·​rate ə-ˈmēl-yə-ˌrāt  -ˈmē-lē-ə-

ameliorated; ameliorating

Synonyms of ameliorate

transitive verb

: to make better or more tolerable

medicine to ameliorate the pain

intransitive verb

: to grow better

Ameliorate traces back to melior, a Latin adjective meaning "better," and is a rather formal synonym of the verbs better and improve. 

improve, better, help, ameliorate mean to make more acceptable or to bring nearer a standard. 

ameliorate implies making more tolerable or acceptable conditions that are hard to endure.