What is "subrogation"

Subrogation \Sub`ro*ga"tion\, n. [Cf. F. subrogation, LL. subrogatio.] The act of subrogating. Specifically: (Law) The substitution of one person in the place of another as a creditor, the new creditor succeeding to the rights of the former; the mode by which a third person who pays a creditor succeeds to his rights against the debtor.
--Bouvier. Burrill. Abbott.

early 15c., "irregular or unlawful placement of someone in an office," from Middle French subrogation and directly from Latin subrogationem (nominative subrogatio), noun of action from past participle stem of subrogare (see subrogate).

n. (context legal English) The substitution of a different person in place of a creditor.

n. (law) the act of substituting of one creditor for another

Subrogation is a legal doctrine whereby one person is entitled to enforce the subsisting or revived rights of another for one's own benefit. A right of subrogation typically arises by operation of law, but can also arise by statute or by agreement. Subrogation is an equitable remedy, having first developed in the English Court of Chancery. It is a familiar feature of common law systems. Analogous doctrines exist in civil law jurisdictions.