eucalyptus

noun

eu·​ca·​lyp·​tus ˌyü-kə-ˈlip-təs 

plural eucalypti ˌyü-kə-ˈlip-ˌtī  -ˌtē  or eucalyptuses

: any of a genus (Eucalyptus) of mostly Australian evergreen trees or rarely shrubs of the myrtle family that have rigid entire leaves and umbellate flowers and are widely cultivated for their gums, resins, oils, and woods

Examples of eucalyptus in a Sentence

Recent Examples on the Web

There’s the popular cotton percale, smooth and slightly shiny cotton sateen, and more breathable, hot sleeper-friendly materials like eucalyptus or Tencel lyocell. —Blake Bakkila, Architectural Digest, 9 Mar. 2026

While most African lodges are built with wood imported from Brazil, Few & Far uses invasive eucalyptus to help reduce its environmental impact. —Lale Arikoglu, Condé Nast Traveler, 8 Mar. 2026

For a natural alternative, Repel’s lemon eucalyptus spray is a solid choice. —Bestreviews, Mercury News, 5 Mar. 2026

Plants like mint, lavender, eucalyptus, and marigold may repel wasps, and traps can help reduce the colony. —Karen Brewer Grossman, Southern Living, 5 Mar. 2026

Word History

Etymology

borrowed from New Latin, genus name, from Greek eu- eu- + kalyptós "covered," verbal adjective of kalýptein "to cover, protect, conceal"; so named for the operculum that covers the developing buds — more at apocalypse

Note: The genus name was introduced by the French botanist Charles Louis L'Héritier de Brutelle (1746-1800) in Sertum Anglicum, seu Plantae rariores quæ in hortis juxta Londinum, imprimis in Horto Regio Kewensi excoluntur (London, 1788), p. 11. According to E.V. Slee et al., EUCLID: Eucalypts of Australia, 3rd edition (online publication), the specimen of Eucalyptus obliqua which L'Héritier described in Kew Gardens had been procured in 1777 by the botanical collector David Nelson at Adventure Bay, Bruny Island, Tasmania, on James Cook's third voyage to the Pacific.

First Known Use

1801, in the meaning defined above

Kids Definition

eucalyptus

noun

eu·​ca·​lyp·​tus ˌyü-kə-ˈlip-təs 

plural eucalypti -ˌtī 

-ˌtē

or eucalyptuses

: any of a genus of mostly Australian evergreen trees of the myrtle family including many that are widely cultivated for their gums, resins, oils, and useful woods

Medical Definition

eucalyptus

noun

eu·​ca·​lyp·​tus ˌyü-kə-ˈlip-təs 

1

capitalized : a genus of mostly Australian evergreen trees or rarely shrubs of the myrtle family that have rigid entire leaves and umbellate flowers and are widely cultivated for their gums, resins, oils, and useful woods

2

plural eucalypti -ˌtī  -ˌtē  or eucalyptuses : any tree or shrub of the genus Eucalyptus

eucalyptus adjective