eucalyptus

American  

[yoo-kuh-lip-tuhs] / ˌju kəˈlɪp təs /

Also eucalypt

noun

eucalypti, plural eucalyptuses plural

1. any of numerous often tall trees belonging to the genus Eucalyptus, of the myrtle family, native to Australia and adjacent islands, having aromatic evergreen leaves that are the source of medicinal oils and heavy wood used as timber.

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eucalyptus British  

/ ˌjuːkəˈlɪptəs, ˈjuːkəˌlɪpt /

noun

1. any myrtaceous tree of the mostly Australian genus Eucalyptus, such as the blue gum and ironbark, widely cultivated for the medicinal oil in their leaves ( eucalyptus oil ), timber, and ornament

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Other Word Forms

Derived Forms

• eucalyptic
  adjective

Inflected Forms

Nouns

• eucalypti
  plural
• eucalyptuses
  plural

Etymology

Origin of eucalyptus

1800–10; < New Latin < Greek eu- eu- + kalyptós covered, wrapped, akin to kalýptein to cover

Explanation

Eucalyptus is an Australian plant that produces an oil with a strong, distinctive scent. Koalas are famously fond of eating eucalyptus leaves. There are more than 600 species of eucalyptus trees and shrubs, many of which are known in their native habitat of Australia and Tasmania as "gumtrees." Most North American eucalyptus is raised for its astringent scent, or for use in cut flower arrangements. The word eucalyptus was coined by an 18th-century French botanist, from the Greek eu, "well," and kalyptos, "covered," a description of the plant's flower bud.

Example Sentences

See Examples For:

eucalyptus eucalypti eucalyptuses

A largely sedentary and inflexible creature, dependent on eucalyptus leaves for much of their water, koalas quickly develop dehydration when hotter conditions persist.

From Barron's ● May 26, 2026

This San Diego weirdness only has tall eucalyptus as witnesses in the park.

From Salon ● May 9, 2026

Allbirds pioneered the use of sustainable materials such as merino wool and eucalyptus tree fiber in footwear and other athletic gear.

From The Wall Street Journal ● Apr. 15, 2026

Common examples include species of acacia, eucalyptus, poplar, and pine.

From Science Daily ● Feb. 9, 2026

A giant eucalyptus tree and a water well, Bir El-Shami, marked the ramp that led to a higher field ending with Grandma Fatima’s home.

From "Tasting the Sky" by Ibtisam Barakat

As the orange ball of the sun rose on the horizon and birds twittered in the eucalypti, Baumgarten showed up—a fit, poised, attractive guy in his 40s.

From Golf Digest ● Apr. 2, 2020

Hasn't California many eucalyptus trees originally brought from Australia, and among the California eucalypti can't some of the twelve varieties the Koala feeds upon be found?

From Time Magazine Archive

A hot sun blazed over Skhirat, where King Hassan II's rambling white summer palace is set amid oaks, poplars and eucalypti beside the Atlantic, and cooling breezes wafted in from the ocean.

From Time Magazine Archive

The correct plural of "eucalyptus" is "eucalypti", without any final "s", the name being treated as a Latin noun of the second declension.

From Writings in the United Amateur, 1915-1922 by Lovecraft, H. P. (Howard Phillips)

The massive stems of many of the eucalypti were between thirty and forty feet in circumference and over a hundred feet in height.

From The Last Voyage to India and Australia, in the 'Sunbeam' by Pritchett, R. T. (Robert Taylor)

In the park, roughly 400 trees, mostly non-native — and notoriously flammable — eucalyptuses, were considered part of the cultural historic landscape.

From Los Angeles Times ● May 4, 2025

Like many other very large trees in L.A. — the eucalyptuses, the bunya-bunyas, the Moreton Bay figs — it hails from Australia.

From Los Angeles Times ● Jan. 29, 2024

Loosely modeled on cactuses, palms, pines and eucalyptuses, they are tucked between bowling alleys and sewage treatment plants.

From New York Times ● Sep. 2, 2021

Redwoods, madrones and manzanitas will be replanted, Mr. Rivail said, but not eucalyptuses, which he called “tinder boxes with oils.”

From New York Times ● Jul. 29, 2021

Since eucalyptuses are particularly resistant to fire, they spread far and wide while other trees and shrubs disappeared.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari