Requel vs. Prequel

A movie which revisits the subject matter of an earlier film but is not a remake or a linear continuation of its plot (i.e. a sequel or prequel).

A prequel is a literary, dramatic or cinematic work whose story precedes that of a previous work, by focusing on events that occur before the original narrative. A prequel is a work that forms part of a backstory to the preceding work.

a story or film containing events which precede those of an existing work

A literary, dramatic, or cinematic work whose narrative takes place before that of a preexisting work in the same series.

(narratology) In a series of works, an installment that is set chronologically before its predecessor, especially the original narrative or (perhaps improper usage) any narrative work with at least one sequel.