The phrase typically refers to promotional collections of films that either bypassed traditional age-rating systems or contain "uncut" footage deemed too intense for standard theatrical releases. Understanding "Unrated" and "18+"
An "unrated" film is a version that was not submitted to the for a formal rating, or it is an uncut version of a movie that originally received a rating like PG-13 or R.
: Often found in various unrated "un-cut" formats, George A. Romero's masterpiece is famous for its practical effects and social commentary. Fifty Shades of Grey (Unrated Edition)