Orbiculate /(?)/

Or·bic·u·late

Orbiculate

n.
  1. That which is orbiculate; especially, a solid the vertical section of which is oval, and the horizontal section circular.

Orbiculate

a.
  1. Made, or being, in the form of an orb; having a circular, or nearly circular, or a spheroidal, outline.

Phrases & Compounds
Orbiculate leaf
a leaf whose outline is nearly circular.