What are the meanings associated with the Radicals? For example, the 大 radical means “big” but the ョ radical means “Wolverine”?? It can’t possibly actually mean that in Japanese does it? Are all of these meanings just arbitrarily assigned to each radical?
The term radical in wanikani is actually a bit confusing. This is a list of the actual “official” radicals and their meanings. Wanikani doesn’t adhere to the official/common meanings and often uses their own ones. In addition, there are many more radical cards in wanikani. They are just used as a vehicle to break down the meanings of complex kanji and to guide progression
You can of course add your own synonyms if that works better for you, but that also means you will have to come up with your own mnemonic for every kanji that uses these.
Keep also in mind that even for the red (kanji cards) there can be some debate over the meaning that wanikani assigns/uses for them, but it’s also not that important in the long run, even Japanese people sometimes don’t know the meaning of some common individual kanjis themselves, because they are only ever used in conjunction with other Kanji.
The vocab cards (purple) are the ones that always have definite defined meanings and that you will encounter when reading japanese.
Radicals don’t have meanings here on WaniKani. They have “names.” They’re not so much arbitrarily chosen, as they are chosen for being memorable to use in mnemonics.
They don’t always have meanings in Japanese either. Sometimes they are just shapes. They might have originally had some meaning in the original pictographic version thousands of years ago, but over time kanji often get simplified into similar looking shapes and those modern shapes don’t necessarily mean anything in that case.
Leebo already said all you need to know, but there are quite a few similar threads about radicals already, maybe you’ll find more info there: