[v] get better; "The weather improved toward evening." [v] to make better; "The editor improved the manuscript with his changes"
ameliorate, better, improve
aggravate, decline, exacerbate, exasperate, worsen
accommodate, acculturate, adapt, adjust, advance, air, alter, ameliorate, amend, be changed, be converted into, be renewed, better, boost, bottom out, break, break up, bring forward, change, checker, chop, chop and change, civilize, come about, come along