1.That which is due; payment. (Obs. as signifying a material thing.) "When thou receivest money for thy labor or ware, thou receivest thy duty."
2.That which a person is bound by moral obligation to do, or refrain from doing; that which one ought to do; service morally obligatory. "Forgetting his duty toward God, his sovereign lord, and his country."
3.Hence, any assigned service or business; as, the duties of a policeman, or a soldier; to be on duty. "With records sweet of duties done." "To employ him on the hardest and most imperative duty." "Duty is a graver term than obligation. A duty hardly exists to do trivial things; but there may be an obligation to do them."
4.Specifically, obedience or submission due to parents and superiors.
5.Respect; reverence; regard; act of respect; homage. "My duty to you."
6.(Engin.) The efficiency of an engine, especially a steam pumping engine, as measured by work done by a certain quantity of fuel; usually, the number of pounds of water lifted one foot by one bushel of coal (94 lbs. old standard), or by 1 cwt. (112 lbs., England, or 100 lbs., United States).
7.(Com.) Tax, toll, impost, or customs; excise; any sum of money required by government to be paid on the importation, exportation, or consumption of goods. Note: An impost on land or other real estate, and on the stock of farmers, is not called a duty, but a direct tax. (U.S.)
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