ros·​tel·​lum | \ rä-ˈste-ləm How to pronounce rostellum (audio) \
plural rostella\ rä-​ˈste-​lə How to pronounce rostellum (audio) \

Definition of rostellum

: 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

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Other Words from rostellum

rostellar \ rä-​ˈste-​lər How to pronounce rostellum (audio) \ adjective

Examples of rostellum in a Sentence

Recent Examples on the Web 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, "Newly Sequenced Vanilla Genome Could Boost Tiny Global Supply," 23 Dec. 2020

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

First Known Use of rostellum

1686, in the meaning defined above

History and Etymology for rostellum

New Latin, from Latin, diminutive of rostrum beak

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Time Traveler for rostellum

Time Traveler

The first known use of rostellum was in 1686

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Cite this Entry

“Rostellum.” Dictionary, Merriam-Webster, Accessed 21 Apr. 2021.

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More Definitions for rostellum


ros·​tel·​lum | \ rä-ˈstel-əm How to pronounce rostellum (audio) \

Medical Definition of rostellum

: an anterior prolongation of the head of a tapeworm often bearing hooks

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