Duty

Webster's Dictionary of the English Language

·noun That which is due; payment.

II. Duty ·noun Respect; reverence; regard; act of respect; homage.

III. Duty ·noun Specifically, obedience or submission due to parents and superiors.

IV. Duty ·noun Hence, any assigned service or business; as, the duties of a policeman, or a soldier; to be on duty.

V. Duty ·noun That which a person is bound by moral obligation to do, or refrain from doing; that which one ought to do; service morally obligatory.

VI. Duty ·noun Tax, toll, impost, or customs; excise; any sum of money required by government to be paid on the importation, exportation, or consumption of goods.

VII. Duty ·noun 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).