Duty

1. Tax, toll, impost, or customs; excise; any sum of money required by government to be paid on the importation, exportation, or consumption of goods.
2. Specifically, obedience or submission due to parents and superiors.
3. That which a person is bound by moral obligation to do, or refrain from doing; that which one ought to do; service morally obligatory.
4. Respect; reverence; regard; act of respect; homage.
5. 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).
6. That which is due; payment.
7. Hence, any assigned service or business; as, the duties of a policeman, or a soldier; to be on duty.