Slice of life is a depiction of mundane experiences in art and entertainment. In theater, slice of life refers to naturalism, while in literary parlance it is a narrative technique in which a seemingly arbitrary sequence of events in a character’s life is presented, often lacking plot development, conflict, and exposition, as well as often having an open ending.
Jeanne Dielman, 23, quai du Commerce, 1080 Bruxelles (1975) is often considered to be a prime example, I think.