An eyeline match is a film editing technique associated with the continuity editing

Continuity editing

Continuity editing is the predominant style of film editing and video editing in the post-production process of filmmaking of narrative films and television programs...

 system. It is based on the premise that the audience will want to see what the character on-screen is seeing. The eyeline match begins with a character looking at something off-screen, there will then be a cut to the object or person at which he is looking. For example, a man is looking off-screen to his left, and then the film cuts to a television that he is watching.

Alfred Hitchcock

Alfred Hitchcock

Sir Alfred Joseph Hitchcock, KBE was a British film director and producer. He pioneered many techniques in the suspense and psychological thriller genres. After a successful career in British cinema in both silent films and early talkies, Hitchcock moved to Hollywood...

's Rear Window

Rear Window

Rear Window is a 1954 American suspense film directed by Alfred Hitchcock, written by John Michael Hayes and based on Cornell Woolrich's 1942 short story "It Had to Be Murder"...

, for example, makes frequent use of eyeline matches. The main character, James Stewart

James Stewart (actor)

James Maitland Stewart was an American film and stage actor, known for his distinctive voice and his everyman persona. Over the course of his career, he starred in many films widely considered classics and was nominated for five Academy Awards, winning one in competition and receiving one Lifetime...

, is confined to his apartment and often looks out its rear window at events in the buildings across from him. Hitchcock frequently cuts from Stewart looking off-screen to the focus of his gaze.