Английский Этимологический словарь - adept (adj.)

- 1663, from L. adeptus, pp. of adipisci "to attain to, acquire," from ad- "to" + apisci "grasp, attain" (related to aptus "fitted"), from PIE *ap- "to take, reach." Meaning "one who is skilled in the secrets of anything" (originally alchemy) is from 1685.