Q&A: Alumnus, platypus, octopus plurals?

Each week here at the Australian Writers’ Centre, we dissect and discuss, contort and retort, ask and gasp at the English language and all its rules, regulations and ridiculousness. It’s a celebration of language, masquerading as a passive-aggressive whinge about words and weirdness. This week, it's one for all the Latin lovers out there…

Q: Hey AWC, my friend was reading her old university’s magazine and she had a question.

A: Was it “why haven’t I achieved as much in my life as all these people featured?”

Q: Ouch, harsh. No, it was what do you call someone who has graduated. It’s an “alumni” magazine – but is that the plural?

A: Ah yes, good question. And this is one for all the Latin lovers out there.

Q: Oh, really? What, like Antonio Banderas or Rudolph Valentino?

A: Um, no. Lovers of the Latin language.

Q: Oh, yes, that makes more sense.

A: The word “alumni” is positively dripping in Latin-ness.

Q: Eww.

A: We mean that its form is very Latin. “Alumni” is indeed the plural form of “alumnus” – just as we have radius and radii, or focus and foci.

Q: And platypus and platypi…

A: Actually, we’ll come back to that. First, let’s just say that “alumnus” in Latin means “foster son” or “pupil” and turned up in English in the 1600s. Macquarie Dictionary defines it as “a graduate or former student of a school, college, university, etc.”

Q: Seems pretty straightforward.

A: Yes – you can be an “alumnus” of a college for example. And in doing so, you can be a part of that college’s “alumni” – the group of former students. We use “alumni news” here at AWC to refer to such awesome people.

Q: Such awesome people.

A: Amazing.

Q: Winners, every one.

A: Anyway, now at this point, for your friend, there is a distinction that can be made – and it’s a question of style.

Q: Well, she doesn’t really wear the same stuff as she did in Uni. That was all long coats, berets and purple Doc Martens…

A: No, we meant style as in a house style or writing style guide. Some use “alumnus” just for male graduates.

Q: So, what are female ones called then?

A: “Alumna” – meaning “foster daughter”.

Q: Oh, okay. So there are two words with the same plural “alumni”?

A: Actually, “alumna” has its own plural – “alumnae”…

Q: Huh? When would you need to use this?

A: It’s female-specific remember, so if it were an all female institution or grouping of all female graduates, the plural “alumnae” may be used.

Q: But I’d still use “alumni” if it were a mix of genders?

A: Correct. Oh, and by the way, all these foster sons and daughters come from the “fostering mother” – or Alma Mater – which in America is often used as the place from which you graduated.

Q: So, why were we coming back to the platypus and platypi?

A: Well, because people love to turn anything ending in “-us” into an “-i” plural. Most Latin words such as “opus” (plural is opera) or “omnibus” don’t actually work that way because they’re in a different family of Latin words.

Q: Wait, what? Latin has different families?

A: Yep, five of them, called declensions. And only the nouns that sit in the “alumnus” family (the second declension) get the “-i” plurals.

Q: So “platypus” isn’t in that family then?

A: It’s not in ANY of them – it’s originally from Greek! But things get muddy because even though it started out with the Greek “-ous” spelling, it was retrofitted into the Modern Latin “-us”. The widely accepted plural is “platypuses” but you’ll also find “platypi” because of this retrofit.

Q: What about “octopus”?

A: An almost identical story, Greek origins, “-ous” spelling changed to “-us”. And again, dictionaries prefer you to use “octopuses” but “octopi” is also listed.

Q: This is all Greek to me.

A: Indeed.

Q: Anyway, thanks for the explanation but I need to leave if I’m going to catch two bi home… oops, I mean buses…

If you have a grammar gripe or punctuation puzzle that you’d like our Q&A to explore, email it to us today!