bipennate

B3I1P3E1N1N1A1T1E1

adjective

Of, pertaining to, or having the nature of a muscle, the fibres of which attach to a tendon on two sides (as a feather barbed on both sides).

OriginEnglish pennate ← Latin bi- ← Proto-Italic *dwi- →
Scrabble 13
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Meanings

adjectivebipennate (not comparable)
  1. not comparableanatomyOf, pertaining to, or having the nature of a muscle, the fibres of which attach to a tendon on two sides (as a feather barbed on both sides).

    Bipennate muscles have a central tendon with oblique insertion fibers on both sides, eg, the rectus femoris (Figure 1.3c).

    2008, John O'Neill, Musculoskeletal Ultrasound: Anatomy and Technique, page 4
    2 more examples

    It then follows that bipennate muscles generate even more force than unipennate ones of similar volume, and the force increases with the angle of pennation.

    1999, Christopher McGowan, A Practical Guide to Vertebrate Mechanics

    Beneath the deltoid lies the external rotators of the shoulders, including the bipennate infraspinatus and the teres minor (Fig. 5-20B).

    2007, Neal S. Elattrache, Christopher D. Harner, Raffy Mirzayan, Jon K. Sekiya, editors, Surgical Techniques in Sports Medicine, page 50
  2. not comparablebiologyBipinnate (pinnate and having a pinnate leaflet).

    But this Burnet Pimpinella is of a different (Umbelliferous) order, though similarly styled because its leaves are likewise bipennate.

    1897, William Thomas Fernie, Herbal Simples Approved for Modern Uses of Cure, 2006 Gutenberg eBook edition
    1 more example

    Its bipennate leaves are composed of a slightly straightened general petiole, of four partial petioles, situated, two at the extremity of the proceeding, and convergent, two a little lower, and growing almost at right angles; each of them bearing more than twenty pairs of small horizontal petioles.

    1849, Adrien de Jussieu, James Hewetson Wilson, The Elements of Botany, page 501
  3. not comparableHaving two wings; bipennated.

Origin

  1. Proto-Indo-European*dwóh₁
  2. Proto-Indo-European*dwi-
  3. Proto-Italic*dwi-
  4. Latinbi-
  5. Englishbi-
  6. Englishpennate
  7. Englishbipennate

From bi- + pennate.

Full word history & related roots →
Cite this entry
APA

bipennate. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/bipennate

MLA

“bipennate.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/bipennate. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “bipennate,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/bipennate.

Source: bipennate on Wiktionary, CC BY-SA 4.0.