- Botany. a cushionlike swelling at the base of a leaf or leaflet, at the point of junction with the axis.
- Architecture. pulvinar(def 2).
Origin of pulvinus
First recorded in 1855–60, pulvinus is from the Latin word pulvīnus cushion
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Examples from the Web for pulvinus
Tropic response of pulvinus of Desmodium gyrans: Experiment 131.Life Movements in Plants, Volume II, 1919
Sir Jagadis Chunder Bose
The moto-excitability of the pulvinus of Mimosa is greatly modified under the influence of temperature.
In Mimosa excitation is manifested by the contraction of the pulvinus and the consequent movement of the leaf.
In Mimosa, the responsive movement is brought about by a sudden diminution of turgor in the pulvinus.
This is accentuated by the expansion of the upper half of the pulvinus which is normally in a state of compression.
- a swelling at the base of a leafstalk: changes in its turgor pressure cause changes in the position of the leaf
C19: from Latin: cushion
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