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noun du·ty \ˈdü-tē also ˈdyü-\

Simple Definition of duty

  • : something that is done as part of a job

  • : something that you must do because it is morally right or because the law requires it

  • : active military service

Source: Merriam-Webster's Learner's Dictionary

Full Definition of duty



  1. 1 :  conduct due to parents and superiors :  respect

  2. 2 a :  obligatory tasks, conduct, service, or functions that arise from one's position (as in life or in a group) b (1) :  assigned service or business (2) :  active military service (3) :  a period of being on duty

  3. 3 a :  a moral or legal obligation b :  the force of moral obligation

  4. 4 :  tax; especially :  a tax on imports

  5. 5 a :  work 1a b (1) :  the service required (as of an electric machine) under specified conditions (2) :  functional application :  use <got double duty out of the trip> (3) :  use as a substitute <making the word do duty for the thing — Edward Sapir>

off duty

  1. :  free from assignment or responsibility

on duty

  1. :  engaged in or responsible for an assigned task or duty

Examples of duty in a sentence

  1. His primary duty at the event is to take attendance.

  2. If new employees are unable to carry out their duties, they may be fired.

  3. We felt it was our duty to help.

  4. He has a duty to support his family.

  5. They helped her out of a sense of duty.

  6. I'll be ready when duty calls.

  7. Her brother returned from duty overseas.

  8. a twelve-month tour of duty

  9. Many reserve troops were called into active duty.

Origin and Etymology of duty

Middle English duete, from Anglo-French deueté, dueté, from deu due

First Known Use: 13th century

Synonym Discussion of duty

function, office, duty, province mean the acts or operations expected of a person or thing. function implies a definite end or purpose or a particular kind of work <the function of language is two-fold: to communicate emotion and to give information — Aldous Huxley>. office is typically applied to the function or service associated with a trade or profession or a special relationship to others <they exercise the offices of the judge, the priest, the counsellor — W. E. Gladstone>. duty applies to a task or responsibility imposed by one's occupation, rank, status, or calling <it is the judicial duty of the court, to examine the whole case — R. B. Taney>. province applies to a function, office, or duty that naturally or logically falls to one <I felt it was not my province to inquire — Anne Brontë>.

task, duty, job, chore, stint, assignment mean a piece of work to be done. task implies work imposed by a person in authority or an employer or by circumstance <charged with a variety of tasks>. duty implies an obligation to perform or responsibility for performance <the duties of a lifeguard>. job applies to a piece of work voluntarily performed; it may sometimes suggest difficulty or importance <the job of turning the company around>. chore implies a minor routine activity necessary for maintaining a household or farm <every child was assigned chores>. stint implies a carefully allotted or measured quantity of assigned work or service <a 2-month stint as a reporter>. assignment implies a definite limited task assigned by one in authority <a reporter's assignment>.



adjective du·ty

Definition of duty

  1. 1 :  done as a duty

  2. 2 :  being on duty :  assigned to specified tasks or functions <the duty officer>


First Known Use of duty


DUTY Defined for Kids


noun du·ty \ˈdü-tē, ˈdyü-\

Definition of duty for Students



  1. 1 :  something a person feels he or she ought to do because it is morally right <Dad says it's his duty to take care of Grandma.>

  2. 2 :  something a person is required to do by law <jury duty>

  3. 3 :  an action done as part of a job or position <a principal's duties>

  4. 4 :  the time during which a person must do his or her job <The police officer was on duty.>

  5. 5 :  active military service <He returned from duty overseas.>

  6. 6 :  a tax especially on imports into a country

Law Dictionary


noun du·ty

Legal Definition of duty



  1. 1 :  tasks, service, or functions that arise from one's position <performing a police officer's duties>; also :  a period of being on duty — see also jury duty

  2. 2 :  an obligation assumed (as by contract) or imposed by law to conduct oneself in conformance with a certain standard or to act in a particular way <duty of good faith> <a duty to warn of danger> — see also public duty doctrine, special duty doctrine duty of candor \-ˈkan-dər\ :  a duty obligating directors of a corporation to disclose all material facts known to them about a transaction when they are seeking shareholder approval duty of care :  a duty to use due care toward others in order to protect them from unnecessary risk of harm duty of fair representation :  a duty obligating a labor union to represent the employees in its collective bargaining unit fairly and in good faith duty of loyalty :  a duty obligating directors of a corporation to refrain from using their positions to further their own interests rather than the interests of the shareholders (as by self-dealing or fraud) fiduciary duty :  a duty obligating a fiduciary (as an agent or trustee) to act with loyalty and honesty and in a manner consistent with the best interests of the beneficiary of the fiduciary relationship (as a principal or trust beneficiary)

  3. 3 :  tax; especially :  a tax on imports

off duty

  1. :  not engaged in a duty <a police officer who is off duty>

on duty

  1. :  engaged in a duty

Origin and Etymology of duty

Anglo-French deuté indebtedness, obligation, from deu owing, due, from Old French — see due

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