pulvinus definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
noun pl. pulvini
Bot. an enlarged area at the base of a petiole, at a node, or at the base of a panicled branch, producing movement by growth or swelling
Origin: Modern Latin ; from Classical Latin pillow, elevation
pulvinus definition by American Heritage Dictionary
noun pl. pul·vi·ni
A cushionlike swelling at the base of the stalk of a leaf or leaflet.
Origin: Latin pulvīnus, cushion.