1530s (implied in addicted) "to devote or give up (oneself) to a habit or occupation," from Latin addictus, past participle of addicere "to deliver, award, yield; make over, sell," properly "give one's assent to," figuratively "to devote, consecrate; sacrifice, sell out, betray, abandon," from ad "to" (see ad-) + dicere, which was usually "to say, declare" (from PIE root *deik- "to show," also "pronounce solemnly"), but also "adjudge, allot."
"It is a yielding to impulse, and generally a bad one" [Century Dictionary]. Old English glossed Latin addictus literally with forscrifen. Related: Addicted; addicting.
"one given over to some practice," 1909, first in reference to morphine, from addict (v.).