myg·​a·​lo·​morph ˈmi-gə-lō-ˌmȯrf How to pronounce mygalomorph (audio)
plural mygalomorphs
: any of various widely distributed, typically large, ground-dwelling, nocturnal spiders (infraorder or suborder Mygalomorphae) that construct silk-lined burrows or chambers, feed on small animals (such as insects, frogs, or mice), and include the tarantulas and trapdoor spiders
The mygalomorphs comprise some 2,200 species of mostly large burrowers.Norman Patnick
… I wonder what the warmly biophilic E. O. Wilson would do if he found a hairy mygalomorph in his shoe closet.Chet Raymo
often used before another noun
mygalomorph spiders
mygalomorph behavior

Note: Mygalomorphs are considered primitive spiders and are distinguished by two pairs of book lungs, two parallel, downward-pointing chelicerae tipped with venomous fangs, and only one or two pairs of spinnerets.

Word History


from the stem of New Latin Mygalomorphae, suborder name (originally a family name), from Mygale, a spider genus (borrowed from Greek mȳgalê, mȳgaléē "an animal, perhaps the shrew or field mouse," from mȳ-, stem of mŷs "mouse" + galéē "weasel, marten") + -o- -o- + -morphae, feminine plural of -morphus -morphous — more at mouse entry 1, galea

Note: The taxon Mygalomorphae was introduced by the British zoologist Reginald Innes Pocock (1863-1947) in "Liphistius and its bearing upon the Classification of Spiders," The Annals and Magazine of Natural History, Sixth series, vol. 10 (1892), p. 311. The genus Mygale was first proposed by the French zoologist Pierre André Latreille (1762-1833) in Histoire naturelle, générale et particulière des crustacées et des insectes, tome troisième (Paris, An X [1802]), p. 49. The somewhat complex background of the genus name is discussed at the entry mygale in the Oxford English Dictionary, third edition, and (unreferenced there) by Latreille in tome 7, pp. 149-150, of the Histoire naturelle. The application of the animal name to the spider was presumably influenced by the French vernacular name for the shrew, musaraigne, and its Latin source, mūs arāneus, literally "spider mouse"; the shrew was allegedly so called because its bite was thought to be toxic.

First Known Use

1938, in the meaning defined above

Time Traveler
The first known use of mygalomorph was in 1938

Dictionary Entries Near mygalomorph

Cite this Entry

“Mygalomorph.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2024.

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