a. [ad. mod.L. bipinnātus: see BI- pref.2 3 and PINNATE, f. pinna wing.]
1. Doubly or subordinately pinnate; see quot.
1794. Martyn, Rousseaus Bot., xxi. 301. The leaves are doubly winged or bipinnate.
1872. Oliver, Elem. Bot., I. vii. 77. A leaf becomes twice pinnate (bi-pinnate) when the common petiole, instead of bearing leaflets, bears secondary petioles upon which the leaflets are pinnately arranged.
2. Zool. Having feathery appendages in opposed pairs.
18568. W. Clark, Van der Hoevens Zool., II. 63. Tail without spur, bipinnate above.
1868. W. S. O., trans. Ocean World, vi. 142. Pennatulidæ with polypes on bipinnate wings.