ar·bi·tra·tor 
(ärbĭ-trā′tər)
(ärbĭ-trā′tər)n.
A person agreed upon or appointed to judge or decide a disputed issue; an arbiter.
- protist
- protistan
- protistology
- protium
- proto-
- Proto-Algonquian
- protoceratops
- protocol
- protocolar
- protocolary
- protoctist
- protoderm
- protodermal
- protogalaxy
- Proto-Germanic
- protogynous
- protogyny
- protohistorian
- protohistoric
- protohistory
- protohuman
- Proto-Indo-European
- protolanguage
- protolithic
- protomartyr