• WordNet 3.6
    • adj circinate shaped like a ring
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Webster's Revised Unabridged Dictionary
    • a Circinate (Bot) Rolled together downward, the tip occupying the center; -- a term used in reference to foliation or leafing, as in ferns.
    • v. t Circinate To make a circle around; to encompass.
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Century Dictionary and Cyclopedia
    • circinate To make a circle (upon) with a pair of compasses.
    • circinate Circular or ring-shaped: as, a circinate eruption: specifically, in botany, applied to that mode of vernation or foliation in which the leaf is rolled up on its axis from the apex toward the base, like a shepherd's crook, as in the fronds of ferns and the leaves of the sundew; but the term is also sometimes used when the coil simply forms a ring.
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Webster's Revised Unabridged Dictionary
L. circinatus, p. p. of circinare, to make round, fr. circinus, a pair of compasses, from Gr. a circle


In literature:

Circinal: spirally rolled like a watch-spring or a butterfly tongue.
"Explanation of Terms Used in Entomology" by John. B. Smith
Most Ferns are circinate in the bud; that is, are rolled up in the manner shown in Fig.
"The Elements of Botany" by Asa Gray
Leaves circinate in vernation.
"The Manual of the Botany of the Northern United States" by Asa Gray