I always thought this word had a silent “o” and was pronounced ‘possum’. But lately I’ve heard a lot of people call this animal an opossum. So I looked it up and apparently either pronunciation is acceptable. So which article should be used “a” or “an”?
And even though both pronunciations are ‘acceptable’, is there one that is *more *acceptable? I mean even though tomAto and tomOto are both acceptable, people who say tomOto sound goofy (if they’re American). So which is it…silent o or not?
I don’t think it has a silent o, but it does have a variant “possum” without the o. “Possum” is much more common in Australia, where there are a lot more species of the animals than the US.
In my experience, even though I know the “correct” spelling is oppossum, I have always written and pronounced it as possum. I think most Americans do the same, unless they are writing in a scientific context. If I see it written as opossum I pronounce it in my mind with the “o” in front. In writing, I think the convention most follow is an oppossum, a possum.
If you’re not pronouncing the O, then it’s possum. So it’s “an opossum” or “a possum.”
Opossum: hissy, white headed North American marsupial
Possum: brown Australian marsupial.
They’re both marsupials, but they aren’t very closely related otherwise. They’re in different orders. Adding or omitting the “o” changes the meaning, it can’t be done haphazardly. In spoken English and colloquial writing, the “o” is dropped from the white one’s name.
So there is both an opossum and a possum and they are two DIFFERENT animals? That is interesting. My dictionary (American Heritage) only list opossum, but offers the o as optional. The pronunciations are listed as : pos-uhm or o-pos-uhm…but instead of the “o” they have that upside-down e thing, which I can’t seem to find on my keyboard.
So does the American variety play opossum?
Opossums play possum. I have no idea if possums play possum as well. 
Yes, they are different, but they look quite similar. The earliest quotes that The Australian National Dictionary has for the use of the words in Australia are both dated 1770 – Sir Joseph Banks (the naturalist) used the term “opossum”, while James Cook (the captain of the ship) used the word “possum” to describe the animals which were obviously quite like the Virginia opossum, that they both knew about. It’s much the same as the use of terms like “mice” and “rats” to describe marsupials that look like mice or rats, but are very distant cousins of the rodents.
I think the two words are synonyms, though “opossum” is more common in the US and “possum” is commoner in Australia
“Possum” is a widely recognized informal term for the American opossum.
If I wish to specifically convey the silent-o pronunciation for the sake of conversational tone, I will write 'possum, using the apostrophe to reflect omission. If I write opossum, I’m sort of expecting the reader to pronounce the o.
That sounds somewhat reminiscent of the buffalo/bison situation. The animals that once roamed the American plains are officially bison. They’re colloquially referred to as buffalo, though true buffalo are something different.
Or “elk”, which means Alces alces in Europe, the animal called a “moose” in North America, whereas on this side of the pond, “elk” means “wapiti” (Cervus elaphus).
(stupid slow server and short edit window)
I suppose I should say Cervus canadensis, as they’ve apparently decided the North American wapiti is a different species. Many old references will still list it as Cervus elaphus, the same species as the European red deer.
For the written version, I trust that there is no debate that it should be “an opossum”.
For pronunciation: if you are saying “possum” then obviously it’s “a possum”. If you are saying “opossum” then it’s “an opossum.”
Unless of course one is Mr. Bumble, the church beadle from Oliver Twist:
I don’t think you should trust that. A Google battle has 2,680,000 entries for “opossum” but 5,710,000 for “possum”. I think that both the spelling and pronunciation have switched so strongly to possum that opossum should only be considered a minor variant in common spoken and written form.
Please don’t! That’s as bad as writing 'til when you mean till. “Possum” and “Opossum” are the correct spellings.
No. Possum is a perfectly acceptable variant of opossum in all contexts, formal and informal, and has been in use at least since the early 17th century.
Google battles don’t help much here, because “possum” is the preferred form for the Australian animals.
What I meant is that if you write “opossum” it should of course by preceded by “an”, not “a”. If you write “possum” then it would be “a possum”.
I don’t know if I would trust the results of that Google battle. In the 5.71 million entries, it could be that most are referring to the Australian marsupial! (Though unlikely I admit.)
I imagine the dominating results for “possum” were due to use of the phrase “playing possum”, or “play possum”
Googling “possum” -“playing possum” -“play possum” returns only 3,030,000 results, compared to 2,790,000 for opossum, so it is actually pretty even.