— This glossary was compiled and edited by volunteer scientists from multiple scientific disciplines using reputable sources, including the references listed at the bottom of this page. If you don’t find the scientific word, term, or expression you are looking for, let us know in the comment section below, and we will research the word for you, and add it to the glossary. We desperately need editors to flesh this glossary out. If you are interested, please contact jerry.cates@entomobiotics.com:


  • ecdysis (pl. ecdyses): molting or shedding of exoskeleton.
  • ectoparasite: a parasite living on the outside of its host.
  • elbowed antennae: (ref. ants) with first segment elongated, and remaining segments coming off at an angle, as typical in ants, rare in some (e.g., snout) beetles.
  • elytron (pl. elytra): a thickened, horny, or leathery front wing (ref. Coleoptera, Dermaptera, and some Homoptera).
  • emarginate: notched.
  • emergence: the process of the adult leaving the pupal case, or the last nymphal skin.
  • endoparasite: a parasite living within its host.
  • entelegyne (en-TEL-i-jeyn): Gr. εντελης “enteles” = perfect, complete, full + Gr. γυνη = a woman, female; 1. Spider anatomy — a form of spider genitalia such that the female’s external copulatory openings typically include a sclerotized epigynum, whereas the male typically is equipped with relatively complex palpi; 2. Taxonomy — a reference to the clade Entelegynae, which comprises most living spiders; compare with Haplogynae.
  • entire: having a smooth outline, without teeth or notches.
  • epigastric furrow: arachnid anatomy — a transverse groove across the anterior ventral portion of the abdomen.
  • epigyne (EPP-ee-gijn): see epigynum.
  • epigynum (ee-PIDJ-uh-numm): Gr. επι = on, upon, at, by + Gr. γυνη = a woman, female; 1. arach. — the sclerotized region of the female spider, located between the book lungs, and positioned anterior of the epigastric furrow, that covers the internal genitalia.
  • epimeron (pl. epimera): the thoracic sclerite just behind a pleural suture.
  • epiproct: a process or appendage just above the anus, appearing to arise from the 10th abdominal segment.
  • episternum (pl. episterna): the thoracic sclerite just in front of a pleural suture.
  • epistomal suture: the suture on the face, between frons and clypeus (Hymenoptera).
  • exoskeleton: a skeleton, or supporting structure, on the exterior of the body.
  • eye cap: an enlarged basal segment of the antenna that overhangs or caps the compound eye (Microlepidoptera, Lyonetiidae)



anat. = anatomy; arach. = arachnid; behav. = behavioral; biol. = biological (inclusive of all animals and plants); bot. = botanical (inclusive of all plants); Gr. = Greek; L. = Latin; q.v. = L. quod vide = which see; pl. = plural; taxon. = taxonomy; zool. = zoological (inclusive of all animals).


  1. Allaby, Michael, Ed. 1991. The Concise Oxford Dictionary of Zoology. Oxford Press.
  2. Beccaloni, Jan. 2009. Arachnids; Glossary, p. 319. University of California Press, p. 56.
  3. Borror, Donald J. & Richard E. White. 1970. Peterson Field Guides: Insects. Houghton Mifflin.
  4. Gertsch, Willis J., 1979. American Spiders, 2nd Edition: Glossary, pp. 255-260. Von Nostrand Reinhold Company.
  5. Howell, W. Mike, and Ronald L. Jenkins. 2004. Spiders of the Eastern United States; Glossary, Chapter X, pp. 341-348. Pearson Education.
  6. Jackman, John A. 1997. A Field Guide to Spiders & Scorpions of Texas: Glossary pp. 173-177. Texas Monthly.
  7. Kaston, B. J. 1978. How to know the spiders: Index and Pictured Glossary, pp. 267-272. McGraw Hill Company.
  8. Preston-Mafham, Rod. 1996. The Book of Spiders and Scorpions; Glossary, pp. 140-141. Barnes & Noble Books, New York.
  9. Ubick, D., P. Paquin, P.E. Cushing and V. Roth, editors, 2005. Spiders of North America, Chapter 72: Glossary — pronunciation guide. Published by the American Arachnological Society.
  10. Venes, Donald, Ed. 2009. Taber’s Cyclopedic Medical Dictionary, 21st Ed. F.A. Davis Company, Philadelphia.
  11. Williams, Tim. 2005. A Dictionary of the Roots and Combining Forms of Scientific Words. Squirrox Press, Norfolk, England.


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