Sidra Holland is a woman whom Jerry Seinfeld dated in "The Implant".
Elaine Benes tells Jerry that her breasts are fake. Jerry suspects she is right and dumps Sidra. While sharing a sauna at the gym with Sidra, Elaine trips and inadvertently grabs Sidra's breasts in order to break her fall. Elaine then determines that her breasts are in fact real, leading Jerry to take Sidra back. Sidra and Jerry's relationship ends badly because she thinks he sent Elaine into the sauna in order to find out if her breasts were real or not.
In "The Pilot, Part 2," Sidra watches the pilot to Jerry's show with Salman Rushdie.
In "The Finale, Part 2," Sidra recaps about Elaine colliding with her in the sauna. She ends up in a relationship with Jackie Chiles. Chiles confirms that Sidra's breasts are "real, and they're spectacular!".
Sidra Holland was portrayed by Teri Hatcher and is one of three 'Desperate Housewives' dated by Jerry, the others being Brenda Strong and Marcia Cross. Hatcher also starred as Lois Lane on Lois & Clark: The New Adventures of Superman, which aired concurrently with Seinfeld's later seasons. Despite the series's history of Superman references, "The Finale" makes no allusion to Hatcher's role as Lois Lane.