Like how human can actually refer to saiyans, Ginyu, or anything at all which is humanoid and/or not a god.
...except that "human" isn't actually used to refer to anything humanoid and not-godly.
The Japanese word "ningen" is, but insisting on translating it as literally "human" in every single circumstance the word's used is just a case of sticking to an awkward literal translation for the sake of... I don't even know what. You can't call it "accuracy" or "faithfulness to the original" when your translation of choice ignores the most obvious meaning in favor of being overly literal, after all -- it's like insisting on calling Trunks "Tolankusu" and Vegeta "Bejiita" even though we know their names are puns off of English words that aren't spelled like that.
"Ningen" is used in a lot of situations where the English language would use a word like "people" or (as seen with Zamasu) "mortals," not just in Dragonball but in a lot of other anime/manga series. I specifically remember a line in Soul Eater where Death the Kid -- who is explicitly NOT "human" -- is referred to as one of a group of "people (ningen) from the academy," and several lines in episodes of Jojo's Bizarre Adventure I watched recently would sound perfectly natural if the word "ningen" is translated as "people," but super awkward and wrong if it's translated as "human." It's even used in Japanese translations of English expressions that use "people/person/man" rather than "human," so obviously it can translate to those terms too.
Also... from looking it up a bit more just now, it seems that the word's origins are from the term "human world" in Buddhism (as opposed to Hell, the worlds of the gods and demons, etc.; should sound familiar considering Dragonball's setup of the mortal universe, afterlife, Demon Realm, and Kaioshin realm) and it doesn't actually have much of the biological connotation (as in, referring to
Homo sapiens the species rather than people/intelligent beings in general) that the English word "human" does. Basically every translation/online dictionary site lists "man" and "person" as translations alongside "human." So translating it as "human" EVERY TIME seems pretty silly in situations like Ginyu talking about being "the type of
ningen who can change bodies," or Vegeta reverting from great ape to
ningen form, or Zamasu wanting to kill all
ningen. In terms of what-sounds-right-and-makes-sense-in-English, I'd go with "person" or "being" as a translation for
ningen Ginyu's line and "humanoid" or even "man" (as in "man vs. beast") for Vegeta's usage, personally... and of course "mortals" for Zamasu, as almost everyone has already latched on to.
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