habit

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A recurrent, often unconscious pattern of behavior that is acquired through frequent repetition.
• noun An established disposition of the mind or character.
• noun Customary manner or practice.
• noun An addiction, especially to a narcotic drug.
• noun Characteristic appearance, form, or manner of growth, especially of a plant or crystal.
• noun A distinctive set of clothing or style of dressing, especially of a religious order.
• noun A riding habit.
• noun Archaic Physical constitution.
• transitive verb To clothe; dress.
• transitive verb To clothe in a habit, especially a nun's habit.

from The Century Dictionary.

• To dwell; abide; reside.
• 1. To dwell in; inhabit.
• To fix by custom; accustom; habituate.
• To dress; clothe; array.
• noun In petrography, the general appearance of a rock given by the texture and the mode, that is, the mineral composition. Rocks may have the same habit and not agree closely in composition.
• noun A small piece of linen attached to a woman's collar at the back, designed to go under the neck of the dress and keep the collar in place.
• noun A usual or characteristic state or condition; natural condition, attitude, appearance, or development; customary mode of being.
• noun A usual or customary mode of action; particularly, a mode of action so established by use as to be entirely natural, involuntary, instinctive, unconscious, uncontrollable, etc.: used especially of the action, whether physical, mental, or moral, of living beings, but also, by extension, of that of inanimate things; hence, in general, custom; usage; also, a natural or more generally an acquired proclivity, disposition, or tendency to act in a certain way.
• noun In logic, a character which can be separated from its subject, without the destruction of the latter.
• noun External dress; particularly, the costume or dress regularly worn, or appropriate for a particular occasion, use, or vocation.
• noun A costume worn by women when riding on horseback; a riding-habit.
• noun The grade marked by this dress. Entering this grade involves almost entire seclusion from earthly things, and constant devotion to religious exercises. Most Oriental monks do not assume the great habit except at the approach of death, the greater number being vowed to the little habit only.
• noun In Scotland, general report: as, by habit and repute a thief.
• noun The grade marked by this dress. Those who wish to enter this grade have first to pass through the rhasophoria or novitiate. See great habit.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb obsolete To inhabit.
• transitive verb To dress; to clothe; to array.
• transitive verb obsolete To accustom; to habituate.
• noun The usual condition or state of a person or thing, either natural or acquired, regarded as something had, possessed, and firmly retained; ; esp., physical temperament or constitution.
• noun (Biol.) The general appearance and manner of life of a living organism.
• noun Fixed or established custom; ordinary course of conduct; practice; usage; hence, prominently, the involuntary tendency or aptitude to perform certain actions which is acquired by their frequent repetition; ; also, peculiar ways of acting; characteristic forms of behavior.
• noun Outward appearance; attire; dress; hence, a garment; esp., a closely fitting garment or dress worn by ladies.
• noun The distinctive clothing worn commonly by nuns or monks.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• verb To clothe.
• verb archaic To inhabit.
• noun An action done on a regular basis.
• noun An action performed repeatedly and automatically, usually without awareness.
• noun A long piece of clothing worn by monks and nuns.
• noun A piece of clothing worn uniformly for a specific activity.
• noun Customary manner of dress.
• noun An addiction.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an established custom
• noun attire that is typically worn by a horseback rider (especially a woman's attire)
• noun the general form or mode of growth (especially of a plant or crystal)
• verb put a habit on
• noun excessive use of drugs
• noun a distinctive attire worn by a member of a religious order
• noun (psychology) an automatic pattern of behavior in reaction to a specific situation; may be inherited or acquired through frequent repetition