A priest or priestess (feminine) is a religious leader who was authorized to perform sacred rituals of a religion and administer religious rites.
In Ireland on Earth during the 19th century the village Catholic priest was one of the leading figures of the community. The Doctor portrayed Father Mulligan several times in the Fair Haven holodeck program. (VOY episodes: "Fair Haven", "Spirit Folk"). Priests such as Father Fitzpatrick were still prominent figures in Irish society as late as the 24th century. Having traveled back to 2267 from the 24th century, Miles O'Brien wished he was back in Fitzpatrick's parish upon having to face Captain James T. Kirk after a fight with Klingons on Deep Space Station K-7. (DS9 novelization: Trials and Tribble-ations)
A Vulcan priest oversaw the wedding of T'Pol to Koss in 2154. Later that year he took the katra of Surak into his mind from that of Jonathan Archer after Archer brought the (ENT episodes: , "Home", "Kir'Shara").