A Ret dator was the term given by the Vulcan people for chambers set aside for preparation for the rite of Pon farr. These rooms were used by Vulcans to make an inflicted person ready for the ceremony that marked the union between bond mates.
In an alternate reality version of 2260, Spock experienced pon farr and travelled to New Vulcan to mate with his bond mate T'Pring. However, when Sarek took his son to the ret dator, Spock experienced a maddening blood fever and attacked his kin whereupon he escaped to join the Sasaud. (TOS comic: "After Darkness, Part 2")