Here dilogy is defined as "a series of two related works". I can't shake off the feeling that there is a more commonly used word for this. Is there? If yes, what is it?
"diptych", sense 3 : a work made up of two matching parts (ref: Merriam-Webster).
Two works do not a series make. In fact, two of anything do not a series make.
Carlo, however, has the correct answer here: it’s a diptych, which is like a triptych but with two pieces instead of three. Wikipedia has a brief article on it.
Here is more about its etymology, from the OED:
Diptych does enjoy some currency as a work comprising two halves. For example:
Furthermore, award-winning author Dan Simmons often refers to his two-volume stories as diptychs, such as the Ilium and Olympos pair. For example, from Dan’s own website:
And it’s not just Simmons. Here is one critic writing about another pair of novels of Dan’s:
Dyad is commonly used for pairs of things. Here is a dyad of definitions:
There's a whole set of related words with increasing valence: monad, dyad, triad, tetrad, pentad, hexad, etc.
protected by RegDwigнt♦ Nov 12 '12 at 11:11
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