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:


  • haltere [HAWL-teer] (pl. halteres). Diptera: a small knobbed structure on each side of the metathorax, representing the hind wings. These minute dumbbell shaped organs have been modified from hindwings to provide a means of encoding body rotations during flight; they are rapidly oscillated simultaneously with the wings, allowing them to experience forces resulting from body rotations; if the body of the insect rotates about one of its three axes (yaw, pitch or roll), the rotation exerts a force on the vibrating halteres, known as the Coriolis effect, that the insect detects with sensory organs called campaniform sensilla and chordotonal organs located at the base of the halteres; the insect uses this information to interpret and correct its position in space; thus halteres act as a balance and guidance system by providing rapid feedback to the wing-steering muscles, as well as those responsible for stabilizing the head, and this allows flies to perform fast acrobatics maneuvers.
  • habitus [HABB-uh-tuss]. L. habitus = appearance, bearing, nature, character; 1. arach. anat. — general appearance, usu. in ref. to a view that shows the full body and appendages of a specimen, in its normal position.
  • homonym [HOMM-oh-nimm]. Linguistics: one of a group of words that share the same pronunciation but have different meanings, whether spelled the same or not; a more restrictive definition sees homonyms as words that are simultaneously homographs (words that share the same spelling, regardless of their pronunciation) and homophones (words that share the same pronunciation, regardless of their spelling); the relationship between a set of homonyms is called homonymy; examples of homonyms are stalk (part of a plant) and stalk (follow/harass a person) and eft (past tense of leave) and left (opposite of right); a distinction is sometimes made between “true” homonyms, which are unrelated in origin, such as skate (glide on ice) and skate (the fish), and polysemous homonyms, or polysemes, which have a shared origin, such as mouth (of a river) and mouth (of an animal).
  • honeydew [HUH-nee-dew]. Secretion: a sticky liquid carbohydrate rich in simple sugars, secreted by aphids and some scale insects as they feed on plant sap; when their mouthparts penetrate the phloem, the sugary liquid is forced out of the gut’s terminal opening under pressure; honeydew is common as a secretion in hemipteran insects and is often the basis for trophobiosis; certain caterpillars of Lycaenidae butterflies and some moths also produce honeydew; honeydew can cause sooty mold on ornamental plants infested with hemipterans; honeydew is also secreted by certain fungi, particularly ergot; honeydew is collected by certain species of birds, wasps, stingless bees, and honey bees, which process it into a dark, strong honey that is prized in parts of Europe and Asia for its reputed medicinal value; the eusocial wasp Parachartergus fraternus collects honeydew to feed to their larvae.
  • humeral [HEW-murr-ul]. Anat.: pertaining to the shoulder; pertaining to front basal part of a wing.
  • humeral angle. the basal front angle of the wing.
  • humeral bristles. Diptera: bristles on the humeral callus.
  • humeral callus. Diptera: a rounded area on the outer front portions of thoracic notum.
  • humeral vein. A branch of Sc extending into humeral angle of wing.
  • hyaline [HY-uh-leen]. Transparent and colorless, like glass.
  • hypermetamorphosis [hy-purr-mett-uh-MOHR-fuh-suss]. Entomology: a class of variants of holometabolism, that is to say, complete insect metamorphosis, but where some larval instars are distinct from each other; the general case in holometabolous insects such as flies, moths, or wasps is for all larval stages to appear similar and merely grow larger as the insect matures; in hypermetamorphic insects at least one instar, usually the first, differs markedly from the rest; in many hypermetamorphic species, the first instars are numerous, tiny, unusually mobile larvae that only survive by finding their way to a food source; the general term for a mobile first instar is a planidium, from the Gr.  πλάνος (planos) = “roaming”.
  • hyperparasite [hy-purr-PAIR-uh-syte]. A parasite whose host is another parasite.
  • hypopharynx [hy-poh-FAIR-inks]. A median mouthpart structure just in front of the labium.
  • hypopleuron [hy-poh-PLEW-rohn] (pl. hypopleura [hy-poh-PLEW-ruh]). Diptera: A sclerite on the thorax just above the hind coxae.
  • hypopleural bristles. Diptera: a row of bristles on hypopleuron.


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. 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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