It's not too different from the way Wario Land 2 names them.
"the giant snake"
"the giant bee"
"the giant spear man"
At least those names came straight out of the game.
I mean it's no surprise. Wario Land isn't the sort of game series that focuses on naming things. They only do when they need to. Like naming worlds or levels because the name shows up on screen. But it's more about "show, don't tell".
By the way, something somewhat related I've been wondering...
The ghost boss in WL2...
The mission you fight him in is called "Capture the ghost!"
The thing is though... you don't capture it, you beat it. Syrup is the one being captured.
This sort of leads me to believe that the ghost might be called Capture. I.e. "Capture, the ghost"
It's probably just weird phrasing, but I like that idea. Food for headcanon.
And I just noticed Wolfenboss looks very similar to Hakusanbo from the Gegege no Kitaro series, specifically the Manga, 1968, 1985 and 1996 anime versions of him. The 1985 anime incarnation of Hakusanbo in particular looks almost exactly like Wolfenboss except for the robe being brown instead of purple and yellow, different eyes and his ears aren't visible under his hood.