A person with a chemical or psychological dependency on a drug, especially one which is illegal or improperly procured.(noun)
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Use "drug addict" in a sentence
"Except that she’s a drug addict but other than that she is soooooooooooooooooo cool."
"Aloysius recognized him as a local drug addict known as the “Hype,” a nickname for junkies who used hypodermic needles."
"Woody Jordan and Bob Cavanaugh, another veteran of the Murder Task Force, were assigned to defend Kevin Dean, forty-two, a convicted car thief and drug addict who was charged with shooting Officer James Camp during a struggle over the officer’s gun."