Dinah Beth Manoff was born on January 25, 1958. She is an American stage and film actress.

Actress was born in New York City, New York, the daughter of actress/director/writer Lee Grant (nee Lyova Rosenthal) and screenwriter Arnold Manoff. She is of Russian Jewish descent. Manoff is married to Arthur Mortell; they have three sons, Dashiell born in 1997 and twins Oliver and Desi, born on January 18, 2002. She lives on Bainbridge Island, Washington.

In 1980, Dinah won the Tony Award for Best Performance by a Featured Actress in a Play, and the Theatre World Award for her performance in the Broadway play, "I Ought to Be in Pictures". In 1985, Manoff portrayed songwriter Ellie Greenwich in the jukebox musical "Leader of the Pack". Some of her film appearances include "Grease" (1977, as Marty), "Ordinary People" (1980) and "Child's Play" (1988).

On television, Dinah is known for her role as Carol Weston on the sitcom Empty Nest, and her role as Elaine Lefkowitz-Dallas on Soap. She also co-starred in the cable television series State of Grace.