Marian Hall Seldes (August 23, 1928 – October 6, 2014) was an American actress. A five-time Tony Award nominee, she won the Tony Award for Best Featured Actress in a Play for A Delicate Balance in 1967, and received subsequent nominations for Father's Day (1971), Deathtrap (1978–82), Ring Round the Moon (1999), and Dinner at Eight (2002). She also won a Drama Desk Award for Father's Day.
Her other Broadway credits include Equus (1974–77), Ivanov (1997), and Deuce (2007). She was inducted into the American Theater Hall of Fame in 1995 and received the Special Tony Award for Lifetime Achievement in 2010.
