(1):

(a.) Meeting at the edges without overlapping; - said of the sepals or the petals of flowers in aestivation, and of leaves in vernation.

(2):

(a.) Resembling, or serving as, a valve; consisting of, or opening by, a valve or valves; valvular.

(3):

(a.) Opening as if by doors or valves, as most kinds of capsules and some anthers.