Have you tried looking at a Japanese definition?
For example
https://www.weblio.jp/content/%E6%99%AE%E9%80%9A
We'll want to look at the noun / na adjective definitions for your question.
1) いつでもどこにでもあって、めずらしくない・こと（さま）。
Existing everywhere, common.
2) ほかとくらべて特に変わらない・こと（さま）。
Not being different from other things.
3) 特別ではなく、一般的である・こと（さま）。
Not being special.
To me, it's basically both of those English words, and more.
lol, I just realized that I basically didn't even look at what you posted and just read it as 普通 in my head. Probably because I almost never hear anyone use 普段 as a noun or na adjective, though that definition does exist. Usually I hear it used as an adverb, which is not what you were asking about anyway.
As a native Japanese speaker, I would say it could be both, and the context dictates which meaning to apply, but I'd probably use 'everyday' or 'routinely' to translate.
普段着 means everyday clothing. Here, I think it's interchangeable with ordinary clothing or normal clothing. You'd never say 普通着 though.
Another use case I can think of is "普段から..." meaning 'normally', 'ordinarily', or 'routinely/regularly'. Again, the first two are not wrong, but the last one is probably most appropriate.
普段, is it ordinary, normal or both
For context, this is the distinction I'm worried about confusing:
https://www.englishforums.com/English/NormalVsOrdinary/zvjbg/post.htm
Does this sort of distinction exist in Japanese, and if so, which would it be more appropriate to interpret 普段 as?