a swelling at the base of a leaf or leaflet stalk, often glandular or responsive to touch.
A pulvinus (pl. pulvini) is a joint-like thickening at the base of a plant leaf or leaflet that facilitates growth-independent (nyctinastic and thigmonastic) movement. It consists of a core of vascular tissue within a flexible, bulky cylinder of thin-walled parenchyma cells. A pulvinus is also sometimes called a geniculum. Pulvinar movement is cau...
an enlargement below the base of a leaf or leaflet in which changes of turgidity enable the leaf or leaflets to droop or fold. Also a glandular swelling in the axils of the inflorescence axis and primary branches of some grasses. adj. pulvinate
a cushion or pad at the insertion of a stalk on a a stem
(from the article `Zingiberales`) ...characteristics common to all members of the order, as well as some peculiar to each family. Each leaf in the family Marantaceae, for example, has ...
<plant biology> A swelling at the base of the stalk of a leaf or leaflet, often glandular or responsive to touch. ... (09 Oct 1997) ... 
a cushion or pad at the insertion of a stalk on a a stem
a cushionlike swelling at the base of a leaf or leaflet, at the point of junction with the axis. · pulvinar (def. 2).