Xjyuk

In Ancient Greek, diminutives are almost always neuter, regardless of the original noun's gender. This leads to words like paidíon, "small child" (from país "child"), which are neuter even though they refer to people.

In modern German, the same thing happens: Mädchen "girl" (from Magd "young woman") is neuter rather than feminine.

But in Latin, I can't think of any word for an individual human that's not masculine (puer), feminine (femina), epicene(*) (homo), or common(*) (ruricola).

Does any such noun exist? That is, is there any noun that unambiguously refers to an individual human being, but is grammatically neuter?

(*) As Alex B puts it, epicene nouns are fixed as grammatically masculine or feminine, but can refer to a male or female person: a good person, man or woman, is a homo bonus. Common nouns are masculine when referring to a male person and feminine when referring to a female person: a good country-dweller is a ruricola bonus or a ruricola bona.

It depends on how much emphasis you put on "unambiguously refers to an individual human being". I don't know of any examples that are just like παιδίον or Mädchen. Several Latin grammars that I have looked at include short lists of neuter nouns that seem to have been used fairly regularly to refer to human beings, but it seems like most of these words did also have other, non-animate meanings.

Here are the neuter nouns I know of that were used to refer to individual human beings:

• mancipium: a slave (compare servitium/servitia, which I think was only used as a collective noun for slaves, rather than to refer to an individual slave). Could also be used for other possessions/property.



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  delicium: apparently, this word was used as an affectionate or neutral term for a slave child. The exact meaning and usage are I think a bit tricky to understand, since I don't think we have that many examples of its use. It's related to the non-neuter word deliciae.

  
  
  

  The word delicium shows up in Plautus. I found a discussion of the meaning in "Tyndarus' Past: the name Paegnium in Plautus' Captivi", by Katerina Philippides (you can read it in this academia.edu pdf), pages 107-108, which cites Nielsen 1990: 85 and Dixon 2001: 13.

  
  



• scortum: a prostitute. Literally "skin, hide", but apparently rarely used with that meaning.




• prostibulum: a prostitute. Apparently, Isidore used it to refer to a brothel instead.




• acroama, -matis: a performer. It could also be used to refer to aural entertainment.

Other cases

There are so few neuter words referring to humans in Latin that I thought I would discuss a few more types that almost certainly don't fit your criteria.

Since you asked specifically about words that could be used to refer to individual human beings, I don't think auxilia "troops" would count, since my understanding is that it (and also servitia mentioned above) is a plural collective noun for a group of human beings.

I'm also not sure whether the singular neuter noun animal counts, since its meaning is obviously broader than humanity, although it can be used to refer to a human.

Another class of neuter words that I feel a bit unsure about how to explain is affectionate nicknames like mel "honey" and meum cor(culum) "my heart". I found some of these when I was searching for vocative neuter nouns, although I'm not actually sure whether these kinds of terms of endearment were used in the vocative case since it's formally identical to the nominative/accusative case for neuter nouns.

Sources

• Andrews, Ethan Allen, 1857, Grammar of the Latin Language, p. 22




• Madvig, Johan Nikolai, 1859, A Latin Grammar for the Use of Schools, p. 20




• Roby, Henry John, 1876, A Grammar of the Latin Language from Plautus to Suetonius, 3rd Ed., p. 107