Definition of: surrogate

(sûr′ə·gāt) noun
1. One who or that which is substituted for another; a substitute.
2. Brit. A deputy appointed by an ecclesiastical judge to act in his place.
3. A probate judge.
—v.t. ·gat·ed, ·gat·ing
1. To put in the place of another; substitute; subrogate.
2. To appoint (another) to succeed oneself. [<L surrogatus <subrogatus, pp. of subrogare <sub- in place of another + rogare ask]