Intercede is a related term of intercession.
As a verb intercede
is to plead on someone else's behalf.
As a noun intercession is
the act of intervening or mediating between two parties.
Other Comparisons: What's the difference?
To plead on someone else's behalf.
To act as a mediator in a dispute; to arbitrate or mediate.
To pass between; to intervene.
* Sir M. Hale
- I to the lords will intercede , not doubting their favourable ear.
- He supposed that a vast period interceded between that origination and the age wherein he lived.
* intercessation of saints