LOS ANGELES (Reuters) - Frances McDormand left the Oscar stage after winning the Best Actress prize on Sunday (March 4) with a call for an "inclusion rider" - an obscure method to increase film production diversity that she hopes will go mainstream.

The term is not well known in Hollywood, but by early morning on Monday after the awards ceremony, Twitter boasted an #inclusionrider hashtag and a Google search of the term produced more than 10 million hits.

While negotiating a contract, actors and film makers can use their star power to get a studio to hire more women and people of color on the production, McDormand explained backstage after her televised comment, which came in a ceremony notable for its activism.

"I just found out about this last week," McDormand, who won the Oscar for her portrayal of a mother searching for her daughter's killer in 'Three Billboards Outside Ebbing, Missouri', told media backstage.

"You can ask for and/or demand at least 50 percent diversity in not only the casting but also the crew," she added as an example.

University of Southern California professor Stacy Smith mentioned the "inclusion rider" idea in a 2016 talk on the lack of diversity in the film industry. She said that Hollywood'A-listers' could stipulate in their contracts that minor roles be cast to reflect demographics of the real world. Studios could voluntarily do the same thing, she added.