An old word for a movie was a "feature film." A "double feature" is where you pay for one movie but they show two. This is usually to promote a lesser-known movie with the draw of the popular movie.

Just googled for it and got these: “two full-length films shown for a single admission price “ From : http://www.yourdictionary.com/double-feature “double feature:n.A movie program consisting of two full-length films.” http://www.thefreedictionary.com/double+feature “The double feature, also known as a double bill, was a motion picture industry phenomenon in which theatre managers would exhibit two films for the price of one, supplanting an earlier format in which one feature film and various short subject reels would be shown.In a modern context, a double bill refers to an airing of a television program in which two episodes are shown consecutively.” http://www.answers.com/topic/double-feature

Hi, double featurecan mean atypical quality or an important part of somthing or part's of someone's face that you notice when you look at them e.g her eyes are her best feature=attractive