The Collaborative International Dictionary
Surrogation
Surrogation \Sur`ro*ga"tion\, n. [See Surrogate, n., and cf.
Subrogation.]
The act of substituting one person in the place of another.
[R.]
--Killingbeck.
Douglas Harper's Etymology Dictionary
surrogation
1530s, from Medieval Latin surrigationem (nominative surrogatio), noun of action from past participle stem of Latin surrogare (see subrogate).
Wiktionary
surrogation
n. The act or result of surrogate; replacement, substitution