To move or change (something) so as to be in a more effective arrangement or desired condition: adjust the timing of a car's engine; adjust a hearing aid to amplify lower frequencies. To change so as to be suitable to or conform with something else: adjusted the schedule to allow for everyone's vacation plans; adjusted the old monetary figures to account for inflation. See Synonyms at adapt.
In chiropractic medicine, to manipulate (the spine and other body structures) to treat disorders and restore normal function of the nervous system.
To decide how much is to be paid on (an insurance claim).