• Webster's Revised Unabridged Dictionary
    • n. pl Invertebrata (Zoöl) A comprehensive division of the animal kingdom, including all except the Vertebrata.
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Century Dictionary and Cyclopedia
    • invertebrata That one of two great divisions of the animal kingdom (the other being the Vertebrata) which includes animals having no spinal column or backbone. It includes seven of the eight main branches into which Animalia are divisible, namely Protozoa, Cælenterata. Echinodermata, Vermes, Arthropoda, Molluscoidea, and Mollusca. thus leaving only the Vertebrata as the remaining subkingdom, of equal rank only with any one of the others, not with them all collectively. The word, however, no longer retains any exact taxonomic significance, being simply used to designate those animals collectively which are not vertebrated. The primary division of the animal kingdom now made is into Protozoa and Metazoa, and the Vertebrata form one of the divisions of the latter, to be contrasted with any one of the prime divisions of the metazoic Invertebrata, not with the Invertebrata collectively. Both terms (Vertebrata and Invertebrata) originated with Lamarck, about the beginning of the nineteenth century. Also called Evertebrata.
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Chambers's Twentieth Century Dictionary
    • Invertebrata a collective name for those animals which agree in not exhibiting the characteristics of vertebrates
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Webster's Revised Unabridged Dictionary
NL., fr. L. in-, not + vertebratus, vertebrate


In literature:

In leaving the class of insects, we leave all the more highly-organized Invertebrata.
"The Contemporary Review, Volume 36, September 1879" by Various
Carbonic oxide is absolutely harmless for the invertebrata which have no blood.
"The Pros and Cons of Vivisection" by Charles Richet