A person lawfully invested with the power, and charged with the duty, of taking care of a person and/or managing the property rights of another person. Guardians are typically used in three situations; for an incapacitated senior (due to old age or infirmity), for a minor and for developmentally disabled adults.

The power and authority constitutionally conferred upon (or constitutionally recognised as existing in) a court or judge to pronounce the sentence of law, or award the remedies provided by the law, upon a state of facts, proved or admitted, referred to the court or tribunal for decision, and authorised by the law to be the subject of investigation or action by that court or tribunal, and in favour of or against persons who present themselves, or who are brought, before the court or tribunal in some manner sanctioned by law as proper and sufficient.

The term that describes a duty that is enforced by a court and where non-fulfilment may incur a penalty.