I'm looking for a word that signifies the opposite of a serial publication, where a serial publication is described like:
The first novella in a three-part series.
Or:
A quarterly publication.
The British expression "one-off" accurately describes the concept, but it seems more colloquial and dismissive, i.e., something that is meant as a draft or a prototype, than what I'm looking for. Surely this word exists.
A use case would be publishing a short-form comic or zine. Some issues would be serial: it will take 3 or 6 (or at least more than one) issues to cover a storyline. Others will be "one-off": it will only take one issue or strip or panel to cover a storyline.