Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. bĭpennis (-pinnis), e, adj. [bispenna], having two wings, two-winged (very rare): insectum, Plin. 11, 28, 33, § 96 (cf. just before, binis advolat pinnis): plumae, Varr. ap. Non. p. 79, 17.
2. bĭpennis, e (acc. sing. reg. bipennem, Varr. ap. Non. p. 79, 19; Verg. A. 5, 307; 11, 651; Petr. 132, 8; Juv. 6, 657; Claud. in Eutr. 1, 333; Sil. 5, 64: bipennim, only in Ov. M. 8, 766, with the var. lect. bipennem.
Abl. sing. reg. bipenni, Verg. A. 2, 479; Ov. M. 12, 611; Petr. 89, 24; Sen. Herc. Oet. 800; Claud. IV. Cons. Hon. 345; id. Rapt. Pros. 3, 79; 3, 377; Sil. 16, 264; and in prose, Plin. 8, 8, 8, § 26: bipenne, only once, Tib. 1, 6, 47) [bis-pinna].
- I. Adj., having two edges, two-edged: securis, Varr. ap. Non. p. 79, 19: ferrum, Verg. A. 11, 135.
Far more freq.,
- II. Subst.: bĭpen-nis, is, f. (sc. securis; cf. Prisc. p. 652 P.), an axe with two edges, a battle-axe (mostly poet.; only found in the nom., dat., acc., and abl. sing., and in nom. and abl. plur.): bipennis dicitur, quod ex utrāque parte habeat acutam aciem, quasi duas pennas. Pennum autem antiqui acutum dicebant, Isid. Orig. 19, 19, 11; cf. id. ib. 11, 1, 46: a pinnā (quod est acutum) securis utrinque habens aciem bipennis, Quint. 1, 4, 12: correptā dura bipenni Limina perrumpit, Verg. A. 2, 479; 2, 627; 11, 135; id. G. 4, 331; Ov. M. 5, 79; 12, 611; Phaedr. 4, 6, 7; Tac. Agr. 10: duris ut ilex tonsa bipennibus, Hor. C. 4, 4, 57; so Claud. in Eutr. 2, 414; id. Laud. Stil. 1, 231; Plin. 8, 8, 8, § 26; Sil. 16, 264.