Say "quadyssey", not "quadrilogy".

"Trilogy" is a delightful word.

"Quadrilogy" is a blight of the tongue.

"Tetralogy" is clunky. "Quartet" is broad.

I propose the following word:

quad•ys•sey (kwŏd′ĭ-sē) noun

a work of art composed of four distinct works

Notable Quadysseys

Quadysseys seem to be rare.

Please email me if you can vouch for good candidate series.

• Hyperion Cantos
• The Inheritance Cycle
• Long Price Quartet

Plus Ones

Adding a sequel or prequel to a trilogy does not make it a quadyssey.

• Divergent + Four
• Lord of the Rings + The Hobbit
• The Matrix + Resurrections

Polygies

Furthermore, I would change the rest of wiktionary's trilogy companions:

• duology
• trilogy
• quadyssey quadrilogy
• polygy pentalogy
• polygy hexalogy
• polygy heptalogy
• polygy octalogy
• polygy ennealogy
• polygy decalogy
• polygy polylogy

For example, Harry Potter is a 7-part polygy and A Series of Unfortunate Events is a 13-part polygy.

Related reading:

• Tetralogy
• List of feature film series with four entries