Madge Dorita Sinclair (28 April 1938 – 20 December 1995) was a Jamaican American character actress.

Sinclair was born Madge Dorita Walters in Kingston, Jamaica, to Herbert and Jemima Walters. She was a teacher in Jamaica until 1968 when she left for New York to pursue her career in acting.

In 1978 she starred in the movie Convoy as the Widow Maker. She would later receive an Emmy Award nomination for her role as Belle in the miniseries Roots. She went on to a long-running stint in the 1980s as nurse Ernestine Shoop on the series Trapper John, M.D. opposite Pernell Roberts. She received three Emmy nominations for her work on the show, and critic Donald Bogle praised her for "maintaining her composure and assurance no matter what the script imposed on her."