A Trill joined to the Dax symbiont.
Jadzia Dax is the science officer of Deep Space Nine, a Trill woman joined with the long-lived Dax symbiont, and she appears in Star Trek: Deep Space Nine. She is young, bright and playful, but she carries the memories of many lifetimes, including those of the man who was a close friend of Benjamin Sisko.
Because of this, she calls Sisko old man, and the two have a deep and affectionate bond. Her relationships are central to the series, including her long romance with Worf, whom she marries, and her friendship with Julian Bashir and Miles O'Brien. She is adventurous and loves risk, drinking and games, but she is also a serious scientist. She dies in the sixth season, and her death is a heavy blow to her friends.
Jadzia is remembered as a brilliant and joyful character, whose spirit and curiosity brought a special light to the series.