addict

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To cause to become physiologically or psychologically dependent on a habit-forming substance: The thief was addicted to cocaine.
2. v. To occupy (oneself) with or involve (oneself) in something habitually or compulsively: The child was addicted to video games.
3. n. One who is addicted, as to narcotics or a compulsive activity.
4. n. A devoted adherent; a fan: "We are all . . . addicts of change” ( Christopher Lasch).

Century Dictionary and Cyclopedia

1. To devote or give up, as to a habit or occupation; apply habitually or sedulously, as to a practice or habit: used reflexively: as, to addict one's self to the exercise of charity; he is addicted (addicts himself) to meditation, pleasure, or intemperance.
2. To give over or surrender; devote, attach, or assign; yield up, as to the service, use, or control of: used both of persons and of things.
3. Specifically In Roman law, to deliver over formally by the sentence of a judge, as a debtor to the service of his creditor. Synonyms Addict, Devote, Apply, accustom. These words, where they approach in meaning, are most used reflexively. Addict and devote are often used in the passive. Addict has quite lost the idea of dedication; it is the yielding to impulse, and generally a bad one. Devote retains much of the idea of service or loyalty by vow; hence it is rarely used of that which is evil. Addicted to every form of folly; devoted to hunting, astronomy, philosophy. Apply is neutral morally, and implies industry or assiduity: as, he applied himself to his task, to learning.
4. Addicted.

Wiktionary

1. n. A person who is addicted, especially to a harmful drug
2. n. An adherent or fan (of something)
3. v. To cause someone to become addicted, especially to a harmful drug
4. v. To involve oneself in something habitually, to the exclusion of almost anything else.
5. v. obsolete To adapt; to make suitable; to fit.

GNU Webster's 1913

1. obsolete Addicted; devoted.
2. v. To apply habitually; to devote; to habituate; -- with to.
3. v. obsolete To adapt; to make suitable; to fit.

WordNet 3.0

1. v. to cause (someone or oneself) to become dependent (on something, especially a narcotic drug)
2. n. someone who is physiologically dependent on a substance; abrupt deprivation of the substance produces withdrawal symptoms
3. n. someone who is so ardently devoted to something that it resembles an addiction