on·​cid·​i·​um än-ˈsi-dē-əm How to pronounce oncidium (audio) äŋ-ˈki- How to pronounce oncidium (audio)
: any of a genus (Oncidium) of showy tropical American chiefly epiphytic orchids

Example Sentences

Recent Examples on the Web Consider the oncidium, whose delicate sideways sprays of vivid blooms suggest a model mobile by Alexander Calder. Adrian Higgins, idahostatesman, 21 Feb. 2018 This is a variety named Lemon Drop, a type of oncidium orchid. Adrian Higgins, idahostatesman, 21 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'oncidium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


borrowed from New Latin, genus name, from Greek ónkos "bulk, mass, body" + New Latin -idium -idium — more at onco-

Note: The genus name was introduced by the Swedish botanist Olof Swartz (1760-1818) in "Orchidernes slägter och arter upställde af O. Swartz," Kongl. Vetenskaps Akademien Nya Handlingar, tomus 21 (1800), p. 240. The orchid takes its name from the onkidion (glossed with Latin tūberculum "small protuberance") "in reference to a feature of the labellum" ("Slägtet som har sit namn af Ογκιδιον Tuberculum, i afseende på Labelli beskaffenhet …").

First Known Use

circa 1868, in the meaning defined above

Time Traveler
The first known use of oncidium was circa 1868

Dictionary Entries Near oncidium

Cite this Entry

“Oncidium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/oncidium. Accessed 8 Dec. 2022.

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