in·ter·cede 
(ĭn′tər-sēd)
(ĭn′tər-sēd)intr.v. in·ter·ced·ed, in·ter·ced·ing, in·ter·cedes
1. To plead on another's behalf.
2. To act as mediator in a dispute.
[Latin intercēdere, to intervene : inter-, inter- + cēdere, to go; see ked- in the Appendix of Indo-European roots.]
in′ter·ceder n.