Zarabeth

Zarabeth was an inhabitant of the planet Sarpeidon.

She was exiled to her planet's past because members of her family tried to kill the tyrannical leader of her planet. She was transported to a barren Ice Age by use of the atavachron, a time portal. There she lived out her existaence in total isolation.

Spock and Leonard McCoy of the USS Enterprise (NCC-1701) were transported to this era by Mr. Atoz. Zarabeth and Spock fell in love. Spock's emotions were released because in this time period Vulcans had not yet controlled their emotions. Evidentually, Spock would find a door to the portal so they could return to their own period, but Zarabeth could not leave as she would die if she left her time period. (TOS: "All Our Yesterdays")

According to the novel Yesterday's Son, she died 17 years after the events of "All Our Yesterdays"