For wolves they’re both correct, actually… it’s largely a regional difference. I generally prefer “pup” (mostly because “cub” always makes me think bears), and it seems to be the preferred term at least around where I’ve lived. I understand “cub” is much more common in the UK, but I’ve never had cause to take a poll on that. 😀 Most of the scientific literature I’ve read also uses “pup,” but then again most of it was written by Americans so it could be the regional difference again.
(The one that fucks me up real bad is where scientific papers will be like “and here we have a cave painting of an elk from such and such cave” and I’m like uuuuhhhh that is clearly a moose? And it took me an embarrassingly long time to realize that what we call an “elk” here is not what is called an “elk” in Europe it’s a goddamned moose, and a “deer” in some places is actually what we’d consider an “elk” and like… why is ungulate terminology so confusing it’s like playing that game with the three shells and you have to keep your eye on where the goddamned ball is.)
As far as what Derek would call a kid, I think that’d come down to your personal preference. I think a lot of folks in this particular fandom at least feel the whole concept is overdone and hate it, but I think it’s cute as shit. That’s possibly because I’ve been calling human babies “pup” for ages, sort of like how my middle school geography teacher called everyone “Champ” because he hadn’t bothered to learn any of our names. I also kind of like that it’s gender-neutral. Maybe we should consider it the werewolf version of “hen”. 😀
I ran across this by accident while working on another werewolf post, so I hope you don’t mind me weighing in.
Pups are short for puppy, which can refer to any juvenile canine. That includes young wolves. Though, it might only apply to domesticated wolves, I’m not sure.
Cubs refer to large juvenile predatory mammals. So, large cats, bears, wolves, and so on. So, a wolf cub is also a wolf puppy. It just depends on the word you want to use.
Incidentally, juvenile large cats can be referred to as either kittens or cubs, for the same reasons.
Which to use for a werewolf? That’s going to depend. Either one could be valid, but if the person using the term is wanting to imply the child isn’t feral enough, or is too submissive, they might use pup as an insult.
Cub might be used to suggest that this is someone who will be a fully fledged member of the pack one day.
Or, they could just use one word habitually, with no thought behind it. As Thewinterotter pointed out, this is a dialect question. Your character might refer to all juvenile werewolves as pups or as cubs because that’s just the “right” word so, because that’s the word they learned to use for their children.
For what it’s worth, there isn’t a wrong choice here. This is a characterization choice. You can pick the term that you feel fits your characters best. You can’t really pick the wrong one, because they’re both appropriate.
I hope that helps.