Adjectives

(a)usedemployed in accomplishing something“the principle of surprise is the most used and misused of all the principles of war” (H.H.Arnold & I.C.Eaker)
(s)exploited, ill-used, put-upon, used, victimized, victimised(of persons) taken advantage of“after going out of his way to help his friend get the job he felt not appreciated but used”
(s)secondhand, usedpreviously used or owned by another“bought a secondhand (or used) car”