https://en.wikipedia.org/wiki/Novel contains this interesting passage:
The romance is a closely related long prose narrative. Walter Scott
defined it as "a fictitious narrative in prose or verse; the interest
of which turns upon marvellous and uncommon incidents", whereas in the
novel "the events are accommodated to the ordinary train of human
events and the modern state of society".[3] However, many romances,
including the historical romances of Scott,[4] Emily Brontė's
Wuthering Heights[5] and Herman Melville's Moby-Dick,[6] are also
frequently called novels, and Scott describes romance as a "kindred
term". Romance, as defined here, should not be confused with the genre
fiction love romance or romance novel. Other European languages do not
distinguish between romance and novel: "a novel is le roman, der
Roman, il romanzo."[7]
By Walter Scott's definition, JRRT's "novels" are, indeed, Romances.
And
https://en.wikipedia.org/wiki/Novella has this tidbit:
The English word "novella" derives from the Italian "novella",
feminine of "novello", which means "new".
And this bit of history:
The novella as a literary genre began developing in the early
Renaissance by the Italian and French literatura, principally Giovanni
Boccaccio, author of The Decameron (1353).[2] The Decameron featured
one hundred tales (novellas) told by ten people (seven women and three
men) fleeing the Black Death by escaping from Florence to the Fiesole
hills in 1348. This structure would then be imitated by subsequent
authors, notably the French queen Marguerite de Navarre, who wrote a
Heptaméron (1559) that included seventy-two original French tales and
was modeled after the structure of The Decameron.
It then goes on to discuss the differences between short stories,
novellas, and novels, noting several novellas sometimes called novels,
And other issues you may find sufficiently confusing. I certainly did.