What Are Female Kangaroos Called & Other Kangaroo Names

Female kangaroos are called does, jills, or flyers, depending on whom you ask. Males go by bucks, jacks, or boomers. Babies are joeys, and a group is a mob. Those are the quick answers, but the naming conventions around kangaroos run surprisingly deep, touching on Aboriginal linguistics, ongoing taxonomic debates about what even counts as a “kangaroo,” and a reproductive system so unusual it gave rise to its own vocabulary.

The Standard Set of Kangaroo Names

The everyday terms for kangaroos follow conventions shared with several other animals. A female is a doe or jill. A male is a buck or jack. These terms are borrowed from deer and rabbit terminology, reflecting the habits of early English-speaking settlers in Australia who reached for familiar labels. More distinctively Australian are the terms “flyer” for a female and “boomer” for a large male. “Boomer” refers to the size and imposing presence of a fully grown male kangaroo, which in species like the red kangaroo can stand taller than most people and weigh over 90 kilograms. “Flyer” is thought to come from the speed and agility of females, who tend to be smaller, lighter, and faster than males of the same species.

A baby kangaroo is universally called a joey. The term predates its use for kangaroos specifically and was once slang in British English for a small or young creature. It stuck firmly in Australia and is now used for the young of all marsupials, not just kangaroos. Orphaned joeys from species including kangaroos, wombats, possums, and koalas are hand-raised using specially formulated milk substitutes tailored to the species and the joey’s age.¹

Where the Word “Kangaroo” Came From

The word “kangaroo” is one of more than 400 words borrowed from Aboriginal Australian languages into English, alongside “boomerang,” “koala,” “dingo,” and “wombat.”² It was recorded by Joseph Banks during James Cook’s 1770 voyage, taken from the Guugu Yimithirr language spoken near present-day Cooktown in Queensland. The Guugu Yimithirr word “gangurru” referred specifically to a large grey kangaroo species, not to all kangaroos in general.

A persistent myth claims that “kangaroo” means “I don’t understand” in the local language, supposedly a response by Aboriginal people to the baffled questions of English sailors. Linguists debunked this decades ago. Fieldwork with Guugu Yimithirr speakers confirmed that “gangurru” was and remains a genuine word for a type of kangaroo. The misunderstanding story makes for a good anecdote, but it has no basis in the historical or linguistic record.

What Counts as a Kangaroo

Kangaroos, wallabies, wallaroos, pademelons, quokkas, and tree-kangaroos all belong to the family Macropodidae, a name meaning “big foot.” The common-name distinction between a kangaroo and a wallaby is largely about size, not a clean taxonomic line. Generally, the four largest species are called kangaroos: the red kangaroo, the eastern grey, the western grey, and the antilopine kangaroo. Wallaroos fall in between, and everything smaller tends to get called a wallaby. But those labels are casual. Researchers working with macropod remains have documented how much the size-related shape variation within the group can blur what seem like clear taxonomic boundaries.³

Then there are tree-kangaroos, which belong to the genus Dendrolagus and live in the tropical rainforests of Australia and New Guinea. They look quite different from their ground-dwelling relatives, with shorter legs, stronger forelimbs, and long tails for balance in the canopy. Despite the name, they are genuine macropods that evolved back into an arboreal lifestyle after their ancestors had already committed to life on the ground. The same naming conventions apply: a female tree-kangaroo is still a doe or jill, a male is a buck or boomer, and the young are joeys. Pouch life in Lumholtz’s tree-kangaroo lasts roughly 246 to 275 days, with weaning occurring 87 to 240 days after the joey first leaves the pouch.⁴

Life Inside the Mob

A group of kangaroos is called a mob, sometimes a troop or a court, though “mob” is by far the most common term in Australian English and in the scientific literature. Mobs are not tightly bonded family units like a wolf pack. They are loose, fluid associations. In field observations of whiptail wallabies, researchers found that mobs of up to fifty members contained all ages and sexes throughout the year, but seldom if ever were all members together at one time. Instead, the animals split into continually changing subgroups of fewer than ten.⁵

Each mob in that study occupied a home range of about 100 hectares, with slight overlap between neighboring mobs’ ranges. Members of different mobs could mingle peacefully in the overlap zones, but they mostly kept to their own areas. This made the core of each range a kind of undefended but monopolized zone. The system is less about territory and more about familiarity: kangaroos know where their mob tends to be, and they drift back to it, even though the subgroup around them shifts constantly.⁵

Within a mob, males establish a dominance hierarchy mainly through ritualized boxing and wrestling. The largest boomer typically has priority access to does in estrus. Younger and smaller males spar with each other to work their way up the hierarchy, and these bouts are what people picture when they think of kangaroo fighting. Females, for their part, tend to be more tolerant of each other and less concerned with rank. A doe may associate with a loose cluster of other females and their joeys, forming a maternal subgroup within the broader mob.

Why “Flyer” Matters: The Doe’s Reproductive Edge

The term “flyer” for a female kangaroo hints at something practical. Does are leaner and faster than boomers partly because, evolutionarily, their survival depends on outrunning predators while carrying or nursing a joey. But the most remarkable thing about female kangaroos is not their speed. It is their ability to manage multiple offspring at different developmental stages simultaneously.

A doe can have a joey at foot (recently out of the pouch but still nursing), a tiny joey attached to a teat inside the pouch, and a dormant embryo in her uterus, all at the same time. That dormant embryo is held in a state called embryonic diapause, a period of developmental arrest. In kangaroos and wallabies, gestation can be extended for up to eleven months through this mechanism.⁶ The pause is controlled hormonally. In some species, suckling by the pouch joey triggers the release of prolactin, which keeps the embryo dormant. In seasonally breeding species, melatonin levels tied to day length control the pause instead.⁶

Research on eastern grey kangaroos confirmed that once the pouch young is lost or nears the end of its pouch life, cell division resumes in both the dormant embryo and the uterus.⁷ In red kangaroos, researchers showed that injecting progesterone into lactating does could terminate the diapause even while the pouch joey was still present, causing the dormant blastocyst to resume growth within days.⁸ This system gives does a powerful insurance policy: if a joey is lost to predation, drought, or accident, the next one is already waiting to pick up development almost immediately.

The Taxonomic Shake-Up That Changed Kangaroo Names

For a long time, the large kangaroos and many wallabies were lumped together in the genus Macropus, making their scientific names fairly uniform. That changed with a major reassessment published in 2019. Researchers analyzing both molecular and anatomical data recommended splitting the old Macropus into several separate genera. Under this proposal, the red kangaroo and its close relatives (the wallaroos and the antilopine kangaroo) were moved to Osphranter. The smaller whiptail wallaby, agile wallaby, and their kin went into Notamacropus. The swamp wallaby, which had long been recognized as unusual, retained its own genus, Wallabia. Only the grey kangaroos stayed in Macropus proper.⁹

This reclassification has been gradually adopted, though not universally. Some wildlife agencies and older field guides still use the traditional Macropus for everything. For the everyday reader, the practical result is that you may now see the red kangaroo listed as either Macropus rufus or Osphranter rufus depending on the source. Both refer to the same animal. The shift reflects genuinely deep genetic divergences within what was once treated as a single group. The cranial shapes, ecological niches, and molecular distances between the subgroups turned out to be as large as those between other genera that had always been recognized as separate.

Giant Extinct Kangaroos and What They Were Called

The naming conventions extend into the fossil record, where some of the most spectacular macropods lived. During the Pleistocene, Australia hosted kangaroos far larger than any alive today. The short-faced kangaroos, belonging to the subfamily Sthenurinae, included animals estimated at more than twice the mass of the biggest modern red kangaroo.¹⁰ Genera like Simosthenurus and Procoptodon are the best known, with some species likely weighing over 200 kilograms.

Recent work using ancient DNA extracted from fossils tens of thousands of years old has clarified where these giants fit on the macropod family tree. The giant short-faced kangaroo Simosthenurus occidentalis turned out to be closely related not to the large modern kangaroos but to the banded hare-wallaby, a small species that weighs only a couple of kilograms. That tiny animal appears to be the closest living relative of the entire once-diverse sthenurine radiation.¹¹ Meanwhile, the giant wallaby Protemnodon anak grouped firmly with modern Macropus and Wallabia, confirming that it was a genuine relative of today’s large kangaroos and wallabies.¹²

Despite their size, these giants were still macropods, and the same informal naming logic applied. A giant short-faced kangaroo was still a kangaroo because it was large and belonged to the right family. Protemnodon species, despite being called “giant wallabies,” were in some cases as large as modern kangaroos. The labels “kangaroo” and “wallaby” were assigned based on perceived body plans and historical convention, not on any strict size cutoff. Biomechanical analysis of the hindlimb bones of these extinct species suggests their metatarsals and heel bones could have supported hopping even at their enormous size, though how they actually moved remains debated.¹⁰

Kangaroo Meat and the Naming Problem

One area where kangaroo naming gets unexpectedly contentious is the commercial sphere. Kangaroo meat has been sold for human consumption in Australia since the 1990s, and the industry has periodically pushed for a more marketable name. Unlike “beef” for cattle or “venison” for deer, there is no widely accepted culinary term that separates kangaroo meat from the animal itself. Proposals over the years have included “australus” and “kangarly,” none of which gained traction.

The debate is more than cosmetic. Kangaroo is Australia’s national emblem animal, and some Australians find eating it uncomfortable. The framing of kangaroo consumption has been shaped by competing narratives around environmentalism, nationalism, and animal welfare. One food writer noted that using kangaroo meat, as an indigenous product, qualifies a dish as distinctly Australian.¹³ Proponents argue that kangaroo is leaner, lower in emissions, and more sustainable than beef on Australian rangelands. Opponents raise concerns about the humaneness of wild harvest and the ethics of commercially exploiting a national symbol. The lack of a separate culinary name keeps the animal front and center every time the meat appears on a menu, which works for those who want consumers to think about what they are eating and against those who would prefer a more neutral branding.

Naming Quirks Across Macropod Species

While doe, buck, and joey apply broadly to all kangaroos and wallabies, some species carry additional informal names worth knowing. Wallaroos, the mid-sized macropods that live primarily in rocky hill country, are sometimes called euros, particularly the common wallaroo in arid and semi-arid regions. The name “euro” comes from an Aboriginal word and is used almost interchangeably with “wallaroo” in parts of outback Australia.

Rat-kangaroos (family Potoroidae), despite having “kangaroo” in the name, are a separate family from the true macropods. These small, ground-dwelling marsupials include potoroos, bettongs, and the musky rat-kangaroo, the only macropod-adjacent species that still has a functional first toe and regularly moves on all fours rather than hopping. Their young are also called joeys, and a group can still be called a mob, but the terms boomer and flyer are not typically applied to animals that weigh under two kilograms.

The quokka, sometimes called the world’s happiest animal thanks to its apparently smiling face, is technically a small wallaby in the genus Setonix. It carries all the standard wallaby naming conventions. A female quokka is a doe, a male is a buck, and their tiny offspring are joeys that spend about six months in the pouch. The quokka’s naming is unremarkable, but its fame as a selfie subject on Rottnest Island has made it one of the most recognized macropods outside Australia, which means more people encounter the term “joey” through quokka tourism content than through any field guide.

The diversity of names across these species reflects a broader truth about macropods as a group. With over 40 living species ranging from the two-kilogram musky rat-kangaroo to the 90-kilogram red kangaroo boomer, the family covers an enormous range of body sizes, habitats, and lifestyles. The informal English names applied to them are a patchwork of Aboriginal borrowings, settler-era analogies to European animals, and Australian slang that calcified into accepted terminology over two centuries. None of it was designed. All of it stuck.