pinnule n 1: division of a usually pinnately divided leaf [syn: {pinna}, {pinnule}]
Pinnule \Pin"nule\, n. [L. pinnula, dim. of pinna feather: cf. F. pinnule.] 1. (Bot.) One of the small divisions of a decompound frond or leaf. See Illust. of {Bipinnate leaf}, under {Bipinnate}. [1913 Webster] 2. (Zool.) Any one of a series of small, slender organs, or parts, when arranged in rows so as to have a plumelike appearance; as, a pinnule of a gorgonia; the pinnules of a crinoid. [1913 Webster]