In North America, possum and opossum often mean the same animal: the Virginia opossum. In Australia and nearby regions, possum usually means one of several different marsupials, such as a common brushtail or ringtail possum. For clear formal US writing, opossum is the safest name for the American animal. In ordinary American speech, possum is established usage rather than a zoological emergency.
One missing letter has therefore been asked to perform an unreasonable amount of taxonomic work.
What is the difference between a possum and an opossum?
The short answer depends on where the speaker is standing.
- In the United States and Canada, possum is commonly used as a shortened name for the Virginia opossum, Didelphis virginiana. The two words can refer to the same animal.
- In Australia, New Guinea, and nearby regions, possums are a different group of marsupials. The common brushtail possum, Trichosurus vulpecula, is one familiar example.
- In scientific and formal contexts, American species are normally called opossums, while Australasian species are normally called possums.
That geographic rule is useful, but it is not absolute. Dictionaries record both names for the North American animal, and historical English has been untidy about the distinction for more than four centuries.
What is a Virginia opossum?
The Virginia opossum is the animal most North Americans picture when either word appears: a cat-sized nocturnal mammal with a pointed pale face, dark ears, fifty teeth, and a long, mostly hairless prehensile tail. Its scientific name is Didelphis virginiana.
It belongs to the order Didelphimorphia and the family Didelphidae, the American opossums. The Smithsonian describes it as the only marsupial living north of Mexico. Its natural and expanded range runs from Central America through much of the United States and into southern Canada, including introduced populations along parts of the Pacific coast.
Calling this animal a possum in American conversation does not turn it into an Australian species. It usually means the speaker has used the common shortened form, much as generations of speakers did before the internet began issuing corrections.
What is an Australian possum?
An Australian possum is not one single species. The name covers multiple arboreal marsupials within the order Diprotodontia, distributed across Australia, New Guinea, and surrounding islands. They are marsupials, like American opossums, but they belong to a different evolutionary branch and different taxonomic families.
The common brushtail possum, Trichosurus vulpecula, belongs to the family Phalangeridae. It has a furry tail, rounded ears, and a coat that can range from silver-gray to dark brown. It lives in forests, woodlands, and cities across Australia and was introduced to New Zealand in the nineteenth century.
The eastern ringtail possum, Pseudocheirus peregrinus, belongs to another family, Pseudocheiridae. It has a slim, furred, white-tipped tail that it uses while climbing. Both species may visit suburban gardens after dark, but neither is a Virginia opossum with its first vowel removed.
Possum vs. opossum: a side-by-side comparison
| Record | Virginia opossum | Australasian possums |
|---|---|---|
| Usual name | Opossum formally; possum commonly in US speech | Possum |
| Example | Didelphis virginiana | Common brushtail, Trichosurus vulpecula; eastern ringtail, Pseudocheirus peregrinus |
| Native region | Central and North America | Australia, New Guinea, and nearby islands; some species introduced elsewhere |
| Order | Didelphimorphia | Diprotodontia for the familiar brushtail and ringtail possums |
| Tail | Long and largely hairless | Varies by species; familiar brushtails and ringtails have furred tails |
| Typical setting | Woodland edges, farms, suburbs, and cities | Forests, woodlands, and many Australian urban areas |
The table compares the Virginia opossum with familiar Australian examples. It should not be read as a description of every animal carrying either common name. More than one American opossum species exists south of the United States, and Australasian possums are a diverse collection rather than a single alternative model.
Why do possum and opossum sound almost identical?
The American name came first in English. Merriam-Webster traces opossum to earlier forms including apossoun and opassom, borrowed from a Virginia Algonquian word whose exact original form is uncertain. The dictionary's current evidence dates opossum to 1610 and the shortened possum to 1613.
The initial vowel disappeared through a linguistic process called aphesis: the loss of a short, unstressed sound at the beginning of a word. This was not a recent spelling mistake. Both versions have been circulating since the early colonial record.
English speakers later applied the familiar name to Australasian marsupials that seemed to resemble the American animals. Over time, opossum became the usual formal label for the American family and possum the usual label for the Australasian groups. Everyday American speech kept the shortened form as well, leaving one word doing two jobs.
How do you pronounce opossum?
Both a voiced first syllable and a silent one are recognized in American English. Merriam-Webster gives the pronunciation as (ə-)ˈpä-səm: roughly uh-POSS-um or simply POSS-um.
That means a person may write opossum and pronounce it exactly like possum without contradicting the dictionary. Regional habits vary, and scientific speakers are more likely to articulate the opening vowel. There is no need to stop a conversation and perform a vowel inspection unless the identity of the animal is genuinely unclear.
Is it wrong to call an American opossum a possum?
No. Possum is established informal American usage for the Virginia opossum. It is also the fixed form in the phrase playing possum.
Context determines the clearest choice:
- Scientific, educational, or formal US writing: use Virginia opossum or opossum.
- Ordinary American conversation: possum and opossum are both understood.
- Writing about Australia: use possum and name the species when possible, such as common brushtail possum.
- International comparison: use the full names. Geography is more informative than correcting one letter.
Are possums and opossums related?
They are both marsupial mammals, meaning their young are born at a very early developmental stage and usually continue developing while attached to a teat, often inside a pouch. That shared reproductive strategy does not make the animals interchangeable.
Virginia opossums belong to Didelphimorphia, an American marsupial lineage. Familiar Australian possums such as brushtails and ringtails belong to Diprotodontia, the order that also includes kangaroos, wombats, and koalas. Calling them cousins is reasonable at the broad marsupial level. Calling them the same animal with regional spelling is not.
Are there possums in New Zealand?
Yes, but they are introduced common brushtail possums rather than native New Zealand mammals. Australian Museum records note that brushtail possums were introduced during the 1830s. They are protected native wildlife in Australia but became an invasive pest in New Zealand, where they damage vegetation and affect native ecosystems.
This is another reason the simple formula “possums live in Australia” needs a footnote. Common names travel with people, and sometimes the animals travel with them.
Why does Hush Hollow use the word opossum?
Hush Hollow uses opossum as the collection and specimen label because the archive depicts the Virginia opossum. It is the clearest formal name and keeps the animal distinct from Australian possums. The shorter American form still belongs in captions, jokes, speech, and search because it is a real part of the language rather than an error to be confiscated.
The label is therefore precise without becoming fussy: Virginia opossum in the record, possum when the sentence naturally calls for it, and the scientific name whenever one missing O threatens to start an international incident.
Frequently asked questions
Is a possum just an opossum without the O?
In everyday North American usage, often yes: possum commonly means the Virginia opossum. In an Australian context, possum usually refers to different marsupial species.
Which animal has the hairless tail?
The Virginia opossum has the familiar long, mostly hairless tail. Common Australian brushtail and ringtail possums have furred tails, although tail form varies across the wider group.
What is the plural of possum and opossum?
Possums and opossums are both standard plurals. Some dictionaries also allow unchanged plural forms, but adding the final s is the clearest choice in ordinary prose.
Should a US writer use possum or opossum?
Use opossum in scientific or formal writing about the American animal. Possum is normal in informal American speech and writing. If readers may be international, Virginia opossum removes the ambiguity completely.
From the archive
The American specimen appears in Opossum Guide, with the correct tail and the full allotment of fifty teeth. Its winter behavior is filed under Do Opossums Hibernate?, its diet under What Do Opossums Eat?, and its involuntary defense under Opossum Playing Dead. The complete drawer is kept in Opossum Shirts. Both American spellings lead there. The Australian possums have retained their own continent and have not been added to the merchandise.
Sources
- Merriam-Webster. Possum vs. Opossum: Is There a Difference?
- Merriam-Webster Dictionary. Opossum: word history and pronunciation.
- Smithsonian's National Zoo and Conservation Biology Institute. Virginia opossum.
- University of Michigan Animal Diversity Web. Didelphis virginiana.
- Australian Museum. Common brushtail possum.
- Australian Museum. Eastern ringtail possum.