Strong's G3315 — μεσιτεύω (verb)
mesiteuo (mes-it-yoo'-o) v.
1. to interpose (as arbiter), i.e (by implication) to ratify (as surety)
[from G3316]
KJV: confirm 
Root(s): G3316 
Hebrew root: μεσίτης
Occurrences: 1