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Related to rostellum: oncosphere, coracidium


n. pl. ros·tel·la (rŏ-stĕl′ə)
A small beaklike part, such as a projection on the stigma of an orchid or the hooked projection on the head of a tapeworm.

[Latin, diminutive of rōstrum, beak; see rostrum.]

ros·tel′lar adj.


n, pl -la (-lə)
(Biology) 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
[C18: from Latin: a little beak, from rōstrum a beak]
rosˈtellate, rosˈtellar adj


(rɒˈstɛl əm)

n., pl. ros•tel•la (rɒˈstɛl ə)
1. any of various small, beaklike parts, as the mouth tube of sucking bugs or the hook-bearing projection of intestinal tapeworms.
2. a beaklike modified stigma of certain orchids that secretes a sticky fluid, enabling pollen grains to adhere to visiting insects.
[1750–60; < New Latin; Latin: little beak, snout, diminutive of rōstrum snout (see rostrum); for formation, see castle]
References in periodicals archive ?
Members of the newly proposed genus Versteria have morphologic features that distinguish them from members of the other taeniid genera, such as miniature rostellar hooks, small scolex, rostellum, and suckers; a short strobili; and a small number of testes (1).
The scolex has four suckers and a conical, retractile rostellum "armed" with 1-8 rows of hooks, depending on the age of the parasite.
2) The majority of orchid flowers attach pollinia indirectly to an adhesive plug (the viscidium) using stalk-like, connective structures produced by the anthers (caudicles) or the rostellum (stipes).