A humanoid species whose strict customs give a father sole charge of any son, who is brought up among men and kept ignorant of women until the age of sixteen.
The Tavnians appear in the Deep Space Nine episode The Muse. Under Tavnian tradition the sexes are separated in childhood. A male child is taken from his mother at birth and raised only by men, and is not even told that women exist until he reaches sixteen.
In 2372 a heavily pregnant Lwaxana Troi arrives at the station, having fled her Tavnian husband Jeyal, who intends to claim the boy she is carrying. She turns to her old friend Odo for shelter.
Odo finds a way out in Tavnian law, under which a child belongs to its mother's current husband. He marries Lwaxana in a Tavnian ceremony, where the groom must declare his love convincingly enough to satisfy the witnesses, Jeyal among them. Odo's speech persuades everyone present, and Jeyal has to accept the result and leave.