Thanks, so Finnegans Wake is considered a modernist novel? Interesting. Totally out of my depth here but it seems so much at odds with modernist ideas in other artistic disciplines, e.g., architecture.
Definitely.
Yes, there are lots of modernisms. Modernism in literature really has very little in common with modernism in architecture, for instance. Even more confusing, each of these modernisms has its own postmodernism, all 'post' their respective modernisms in different ways.
The sort of fragmentation of language and narrative that we see in Ulysses and Finnegans Wake is a pretty central modernist trait, I'd say. An even more central example would be something like Eliot's The Wasteland.
Relevant Wikipedia entry:
https://en.wikipedia.org/wiki/Postmodern_literature
I'd count Joyce as a canonical modernist. (If he isn't, who is?)