pulvinus
/pʌlˈvaɪnəs/
noun
- A swollen joint at the base of a leaf or leaflet in certain plants, allowing movement (e.g., folding or drooping).
- Botanists studied the pulvinus to understand how plants respond to light.
- The mimosa plant's pulvinus makes its leaves close when touched.
- Each leaflet has a tiny pulvinus that controls its angle toward the sun.