ther·​a·​pho·​sid ˌther-ə-ˈfō-səd How to pronounce theraphosid (audio)
: of or relating to a family (Theraphosidae) of mygalomorph spiders that comprises the tarantulas (see tarantula sense 1)
Theraphosid spiders are formidable opponents and are capable of seizing and killing animals as large or larger than themselves …Fred Punzo
Lifespans of a decade or more have been recorded for captive theraphosid spiders.Richard Rowe
theraphosid noun
plural theraphosids
In cage experiments, it has been shown that within 24 hours, a hungry theraphosid can reduce a mouse to nothing but a hard, dry mass of skin, hair, and bones. Martin Nyffeler and Richard S. Vetter

Word History


from the stem of New Latin Theraphosidae, family name, from Theraphosa, a genus (from Greek thēráphion "a kind of insect" —from thḗr "carnivorous animal, beast" + -aphion, diminutive suffix of animals— + New Latin -osa, of uncertain origin) + -idae -idae — more at fierce

Note: The genus name Theraphosa was introduced by the Swedish arachnologist Tamerlan Thorell (1830-1901) in "On European Spiders," Nova acta Regiae Societatis Scientiarum Upsaliensis, Seriei Tertiae vol. VII, fasciculus prior (1869), pp. 162-63. Thorell recycled a taxonomic name used earlier by the French civil servant, author and naturalist Charles Athanase Walckenaer (1771-1852) for a group of spiders including some in the genus Mygale (see note at mygalomorph); Thorell renamed this genus Theraphosa. Walckenaer's taxon Theraphosa (also in the vernacular form Théraphose) was introduced in his Tableau des Aranéïdes (Paris, 1805), p. 2 ff. The suffix -osa is perhaps the feminine of Latin -ōsus "possessing the qualities of" (see -ose entry 1), though the resulting sense of the derivative is unclear.

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of theraphosid was in 1887

Dictionary Entries Near theraphosid

Cite this Entry

“Theraphosid.” Dictionary, Merriam-Webster, Accessed 30 May. 2024.

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