Definify.com

Webster 1913 Edition

Adj.

Of or pertaining to a mediator, or to mediation; mediatory;

as, a

mediatorial

office

–

Meˊdi-a-to′ri-al-ly

adv.

My measures were . . . healing and

mediatorial

Burke.

Adj.

Belonging to a mediator; as mediatorial office or character. [Mediatory is not used.]

mediatorial ‎(comparative more mediatorial, superlative most mediatorial)

Relating to or befitting a mediator (one who mediates).
- 1935, "Anglo-Irish Trade Accords", Montreal Gazette, 7 Feb., p. 10 (retrieved 2 Nov. 2010):
  Whenever a dispute arises between two nations, each insistent upon its own rights and claims, and refusing all mediatorial efforts at compromise, it is usual that the contest develops into a battle of wits and that the essential issue at stake is relegated to the background.