Marvin Palmer Morris "Cyclone Cy" Wentworth (January 24, 1904 – October 10, 1982) was a Canadian hockey player.

In 1926, Wentworth became a professional player with Eddie Livingstone's Chicago Cardinals, a new team in the American Hockey Association (AHA) which intended to rival the NHL.

In Montreal, Cy won his first and only Stanley Cup when his Maroons defeated Toronto in the 1935 finals after eliminating his old teammates from Chicago.

Wentworth was Montreal's leading point-getter in those playoffs with three goals and two assists in seven games.

He played two seasons with the Habs before retiring in 1940, after which he moved to Toronto and became involved in a variety of business interests.