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Alternative forms[edit]


Borrowing from New Latin pyrifōrmis, from pyrum (a pear) +‎ -fōrmis (-form, -shaped, adjectival suffix). Doublet of pyriformis.



pyriform (comparative more pyriform, superlative most pyriform)

  1. (biology) Pear-shaped.
    • 1835, Richard Owen, Descriptive and Illustrated Catalogue of the Physiological Series of Comparative Anatomy Contained in the Museum of the Royal College of Surgeons in London, Volume III Part I: Nervous System and Organs of Sense, pages 25–26:
      The chief difference between this brain and that of the Turtle obtains in the large size of the optic lobe and cerebrum as compared with the cerebellum, in the more pyriform figure of the cerebral hemispheres, and in the transverse fissure of the cerebellum.
    • 1992, Edward Bayler Cutler, The Sipuncula: Their Systematics, Biology, and Evolution, page 145:
      Most small worms have a pyriform shape. Larger worms living in unconsolidated sediments are cylindrical and elongate. Those in rock fissures or coral crevices have stouter and more pyriform bodies.
    • 2006, Reyes Peña-Santiago, “Dorylaimida Part I: Superfamilies Belondiroidea, Nygolaimoidea and Tylencholaimoidea”, in Eyualem Abebe; István Andrássy; Walter Traunspurger, editors, Freshwater Nematodes: Ecology and Taxonomy, page 358:
      In fact, Clavigula is very similar to Glochidorella, differing from this mainly in the absence of perioral disc (vs. presence), shape of pharyngeal bulb (more cylindrical vs. more pyriform) and more robust spicules.
    Synonym: (of bird eggs) peg-top shaped[1]

Derived terms[edit]



pyriform (plural pyriforms)

  1. A pyriform object.


  1. ^ Salim Ali; Sidney Dillon Ripley (1983) Handbook of the Birds of India and Pakistan[1], volume 2, 2nd edition, Oxford University Press, page 214