This is a common term for the closing shot of a movie, the one that lets the audience know that the story is over and it is time to grab your hat and coat and go home. Not terribly obvious when it's there many times, it's remarkably noticeable when it is left out. A fade-to-black or other similar abrupt ending feels abrupt exactly because the audience is used to being given a hat-and-coat shot.
The most common technique for these is to expand the frame. This is a visual metaphor that says we are leaving the narrow focus of this story and turning our attention to a wider context. Panning across the landscape; a crane shot that lifts the camera so that more and more of the city is revealed; backing all the way out to framing the planet in space — all these are hat-and-coat shots that use the same basic visual vocabulary.
Another common technique is to exclude the audience from the movie's world. The shot of the cowboys Riding into the Sunset; the characters walking away down a path or up a staircase; the protagonist going into a house and closing the door — are, again, using a common vocabulary to tell the audience "What happens to these people after this point is not our concern."