rostellum

American  

[ro-stel-uhm] / rɒˈstɛl əm /

noun

PLURAL

rostella

1. Biology.  any small, beaklike process.

2. Botany.  a beaklike modification of the stigma in many orchids.

3. Zoology.

   1. a projecting part of the scolex in certain tapeworms.

   2. a part of the mouth in many insects, designed for sucking.

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rostellum British  

/ rɒˈstɛləm /

noun

1. biology a small beaklike process, such as the hooked projection from the top of the head in tapeworms or the outgrowth from the stigma of an orchid

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Other Word Forms

• rostellate adjective

Etymology

Origin of rostellum

1750–60; < New Latin; Latin: little beak, snout, diminutive of rōstrum snout ( rostrum ); for formation, castellum

Example Sentences

Rostellum: a small beak; applied to the mouth parts of sucking lice: also used in Hemiptera, as = rostrum; q.v.

From Project Gutenberg

Anthera fere immersa, Rostellum integrum ut in omnibus glandula orbotis Pollinia 8. 

From Project Gutenberg

With Spiranthes autumnalis, the pollen-masses cannot be applied to the stigma until the labellum and rostellum have moved apart, and this movement is very slow.

From Project Gutenberg

By the way, Cephalanthera has single pollen-grains, but this seems to be a case of degradation, for the rostellum is utterly aborted.

From Project Gutenberg

I have been much interested by what you say on the rostellum exciting pollen to protrude tubes; but are you sure that the rostellum does excite them?

From Project Gutenberg