routine of behavior that is repeated regularly and tends to occur subconsciously From Wikiquote, the free quote compendium
Habits are automatic routines of behavior that are repeated regularly, without thinking. They are learned, not instinctive, human behaviors that occur automatically, without the explicit contemporaneous intention of the person. The person may not be paying attention to or be conscious or aware of the behavior. When the behavior is brought to the person's attention, they may be able to control it.
Quotes reported in Josiah Hotchkiss Gilbert, Dictionary of Burning Words of Brilliant Writers (1895).
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