— 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:


  • femur (pl. femora): the leg segment between trochanter and tibia.
  • file: a file like ridge on the ventral side of the front wing, part of a sound-making apparatus in certain Orthoptera.
  • filiform: hairlike or threadlike.
  • fontanelle (alt. fontanel, colloquially: soft spot): 1. humans: anatomical feature of the infant human skull comprising any of the soft membranous gaps (sutures) between the cranial bones that make up the calvaria of a fetus or an infant; allows for rapid stretching and deformation of the neurocranium as the brain expands faster than the surrounding bone can grow; 2. termites: a depressed pale spot on the front of the head, between the eyes.
  • flabellate antenna: (ref. Coleoptera) with tonguelike processes on the terminal segments.
  • frenulum: 1. anat. a small fold or ridge of tissue that supports or checks the motion of the part to which it is attached, in particular a fold of skin beneath the tongue, or between the lip and the gum.; 2. insects: a bristle or group of bristles at the humeral angle of the hind wing (Lepidoptera); i.e. in some moths and butterflies, a bristle or row of bristles on the edge of the hind wing that keeps it in contact with the forewing;
  • frons: an area on the face, between frontal and epistomal sutures and including the median ocellus;
  • frontal suture: one of two sutures, on each side of frons; a suture in the form of an inverted U or V, with its apex just above the base of the antennae (Diptera);
  • fronto-orbital bristles: bristles on upper front part of head next to the compound eyes (Diptera).
  • furcula: the furcula (L. = “little fork”) or wishbone is a forked bone found in birds and some dinosaurs formed by the fusion of the two clavicles; in birds, its primary function is in the strengthening of the thoracic skeleton to withstand the rigors of flight; also used as the designation for the forked tail of a springtail (Collembola).


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. and 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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