n. # A set of five works of art that are connected, and that can be seen either as a single work or as five individual works. They are commonly found in literature, film, or video games.
The Century Dictionary and Cyclopedia
n. Five mutually connected parts or principles; a pentad; specifically, a fivefold classification; the doctrine of the fivefoldness of the universe.
Word Usage
"A world famous "questioning" disciple of Sri Aurobindo has accomplished a superhuman feat by rewriting the Master's magnum opus as "The Lives Divine" - a pentalogy."