Initiate

An initiate is a Trill individual who undergoes intense screening by the Trill Symbiosis Commission to ascertain if they are suitable for joining with a Trill symbiont.

Jadzia Dax was originally dismissed from the initiate corps by Curzon Dax, who had fallen in love with her. Jadzia later reapplied after Curzon reconsidered and spent three years training until she was joined with. Dax was the only initiate who was successful in making a second application to the process. 

In the 31st century, the Trill Symbiosis Commission assigned Cretia and Janra to accompany Ambassador on a mission to the Gamma Quadrant aboard a Starfleet transwarp vessel. The pair were assigned in case anything happened to Ambassador Dax and the symbiont was endangered, although Cretia and Janra were killed when the transwarp core of the vessel exploded during the mission. (SS ST (The Law of Averages))