rostellum

noun

ros·​tel·​lum rä-ˈste-ləm How to pronounce rostellum (audio)
plural rostella rä-ˈste-lə How to pronounce rostellum (audio)
: a small process resembling a beak : a diminutive rostrum: such as
a
: an extension of the stigma of an orchid flower
b
: an anterior prolongation of the head of a tapeworm bearing hooks
rostellar
rä-ˈste-lər How to pronounce rostellum (audio)
adjective

Examples of rostellum in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
One of the traits researchers are keenest to explore is one that would eliminate a flap inside the vanilla flowers called the rostellum. — Alex Fox, Smithsonian Magazine, 23 Dec. 2020

Word History

Etymology

New Latin, from Latin, diminutive of rostrum beak

First Known Use

1686, in the meaning defined above

Time Traveler
The first known use of rostellum was in 1686

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“Rostellum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rostellum. Accessed 21 Mar. 2025.

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Medical Definition

rostellum

noun
ros·​tel·​lum rä-ˈstel-əm How to pronounce rostellum (audio)
: an anterior prolongation of the head of a tapeworm often bearing hooks

More from Merriam-Webster on rostellum

Britannica.com: Encyclopedia article about rostellum

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