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Grammar
Course: Grammar > Unit 1
Lesson 5: Irregular plural nouns: mutant and foreign pluralsIrregular plural nouns: foreign plurals
You don't need to know how to speak Latin and Greek in order to understand English, but some words in English come from those languages. It's helpful to know how some Greek and Latin words change from singular to plural.
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- Ok .... The question of the ages . What is the plural of platypus?(39 votes)
- Scientists generally use "platypuses" or simply "platypus". Colloquially, the term "platypi" is also used for the plural, although this is technically incorrect and a form of pseudo-Latin; the correct Greek plural would be "platypodes". If you every come across more than one of these weird looking creatures, keep your distance! The males are venomous.(55 votes)
- If I was using the plural word for octopus would I say octi?(9 votes)
- No. The word is "Octopuses". People also use "Octopi". I hope this helps!(18 votes)
- What in the world is datum? I've never heard of it before(9 votes)
- Datum is the singular form of data, which is plural. You just don't see "datum" very often because it is much more common to have many pieces of data, instead of just one.
This is one of those things that you can file away in your mind as "good to know" - the main thing to remember is which verb to use with each form:
- datum is (singular)
- data are (plural)
Hope this helps!(14 votes)
- Why are they called "Romance languages"?(5 votes)
- Spanish, Portuguese, French, Italian, Romanian, and Catalan are all languages that are descendants of Latin, the language spoken by the Romans.(15 votes)
- How about organism? The word 'organisms' or 'organia' is more often?(5 votes)
- Hi Amy! I'd say the plural "organisms" is the most accepted and used plural form of "organism."(13 votes)
- Would it be easier to understand foreign nouns by learning Latin and Greek?(8 votes)
- I concur with the answer by Madeliv. However, I, from my personal experience, would recommend learning French first, then Latin, and then Greek, i.e. Ancient Greek, if you do indeed intend to embark on learning these languages.(2 votes)
- Would the regular plurals of these words be considered correct?(5 votes)
- No, people might understand you (thanks to the context) but it would be considered incorrect. If you say:
I have 5 mouses
native speakers of English would find this odd, and wrong, but probably still understand that you meant mice.(10 votes)
- If you were talking to someone that didn't know foreign plurals, how would you explain that?(3 votes)
- I would refer them to the excellent video about foreign plurals found on the Khan Academy website. What would YOU do?(10 votes)
- Do I always have to say "cacti" or can I still say "cactuses" when talking and writing.(6 votes)
- When you write in formal writing, you would say or write cacti. In informal writing you could say or write cacti or cactuses. I would prefer cacti.(1 vote)
- Is it okay to data as Da-Ta or It would be best to say it as Day-Ta?(5 votes)
- There are three pronunciations. All of which are acceptable. See https://www.dictionary.com/browse/data(1 vote)
Video transcript
- [Voiceover] Hello grammarians! Today we're talking about another kind of irregular plural noun, and that is the foreign plural. Those are words that are
borrowed into English from some other language. Words like fungus, or cactus, or thesis, or criteria. And these words come from Latin and Greek, respectively, but don't get the idea
that you need to learn to be able to speak Latin or Greek in order to speak English. No, not at all. But while some words that
got borrowed into English have lost their language-specific plurals, some have not. Some have maintained those plurals. And it kind of depends on which situation you're using them in. So, for example, in an informal context, it would be perfectly acceptable for you or me to say funguses, like that. But if I was talking to a biologist, she would probably say fungi if she were talking about
them in a scientific context. Just like it's okay in informal speech to talk about cactuses. You're driving along a road in Arizona, you see a lot of cactuses. But, again, if you studied
cactuses for a living, you would probably call them cacti. It's more precise, it's more formal. If you like, it's more polite. Now, my feeling is, that
as fungus and cactus get more and more entrenched into English eventually these formal
endings are going to fall away and we're just gonna
have this regular plural. But for now there are still
some pluralizing rules for other languages that it helps to know. So let's go through those. So I made this little chart to go over the six most common Latin
and Greek irregular plurals that you're going to encounter in English. So the first one is final -a to final -ae. So you take a word like
larva in the singular, which is like a little baby bug, like an ant larva, or a caterpillar larva, and the traditional irregular plural, the Latin plural of that, is larvae, -ae. But the regular plural
that will probably get more popular over time is larvas. But this is the first one, -a to -ae. Larva to larvae. Just like antenna becomes antennae. Secondly the ending change
from final -us to final -i, which we find in a word like
fungus, is the singular, and then the irregular
plural of that is fungi. And, as I said before,
there are some people who use funguses, but
again, that regular plural is more informal. This next one is also Latin and it's the change from
final -um to final -a. So we take a word like
datum, which is a single unit of data, so the plural of data, so we change singular datum to plural data and there is no accepted,
you wouldn't say the datas, that is not an accepted regular plural. I think what's going to
happen instead is that datum is gonna fall away. But, again, it hasn't really happened yet. Not in a formal context, anyway. This next one is also Latin,
and it's final -ex or final -ix to final -ices. So if you take a word
like index, or matrix, the plural of that is
not indexes, but indices. Indexes is, again, the
informal regular plural, but indices is the more
formal irregular plural. Likewise, matrices. This one is Greek and it's the change from final -is to final
-es, as in the word thesis in the singular becoming
theses in the irregular plural. The regular plural of
this I do not care for because it is thesises, and
I think that sounds silly. But thinking something
is silly is no reason to stand athwart the tide
of linguistic change, grumble grumble. This last one is also Greek,
and it's the change from singular -on to plural -a. So we this word like
criterion, or phenomenon, and in the plural it is
criteria or phenomena. (singing) Do do do do do. And as with datum, there isn't really a regular plural form for criteria. Nobody says criterions,
because the word criteria is so much better known. Anyway, so these are
six little ending rules, but, like I said, you don't
need to learn Latin or Greek in order to make sense of English. But having these six
rules in your tool belt, if you use them judiciously, will probably come in handy. But, for real, if you see
a word and you don't know it's derivation, just trust your instincts and give it a regular plural. Just tack on an -s. You know, the world's not gonna end, not harm will come to you. And if you're curious,
you can look it up later. You can learn anything. David out.