Definition of pulvinus in English:

pulvinus

Pronunciation /pəlˈvīnəs/ /pəlˈvaɪnəs/

nounpulvini

Botany
  • An enlarged section at the base of a leaf stalk in some plants that is subject to changes of turgor, leading to movements of the leaf or leaflet.

    ‘Leaves move by means of turgor pressure changes at the pulvinus at the base of each lamina.’
    • ‘Soluble proteins were extracted from gravistimulated pulvini and subjected to protein phosphorylation reactions.’
    • ‘The ion flux occurs within seconds after gravistimulation and establishes pH gradients across roots and maize pulvini.’
    • ‘When the promoter fragment was resolved into smaller portions, further elements could be identified that conferred root, pulvinus and anther expression.’
    • ‘With the exception of petiole length, pulvinus length and stipule length, the other leaf characteristics overlap between the two species.’

Origin

Mid 19th century from Latin, literally ‘cushion’.