Definition of invertebrate in English:



  • An animal lacking a backbone, such as an arthropod, mollusc, annelid, coelenterate, etc. The invertebrates constitute an artificial division of the animal kingdom, comprising 95 per cent of animal species and about thirty different phyla.

    Compare with vertebrate
    • ‘Insects, spiders, and other invertebrates make up most of the Hermit Warbler's diet.’
    • ‘It is typical of vertebrates but rare among invertebrates, being seen in a few molluscs and arachnids.’
    • ‘They feed by sucking juices from soft-bodied invertebrates through a long proboscis.’
    • ‘Other invertebrates, including mollusks and crustaceans, are also part of the diet.’
    • ‘In the spring, their diet includes a higher proportion of invertebrates such as insects and snails.’
    • ‘Smaller vertebrates and invertebrates are also known in abundance from France and Bavaria.’
    • ‘Insects and other aquatic invertebrates are also eaten, especially by young birds.’
    • ‘In many cases, the adhesive gels secreted by invertebrates are described as mucus.’
    • ‘Living horseshoe crabs feed on molluscs, worms, and other tasty and nutritious marine invertebrates.’
    • ‘The saw is also used as a digging tool to probe in mud and sand in search of crustaceans and other small invertebrates.’
    • ‘Fish eat snails in their shells and hard-shelled crustacea as well as invertebrates with exoskeletons.’
    • ‘While studies have been done in mammals and other vertebrates less is known of invertebrates.’
    • ‘Aquatic invertebrates are also eaten, especially by breeding females and the young.’
    • ‘The exhibit is currently home to more than 70 species of fish, invertebrates and corals.’
    • ‘North American river otters are important predators of fish and aquatic invertebrates.’
    • ‘These distinctions correspond closely to our distinction between vertebrates and invertebrates.’
    • ‘During the breeding season they eat mostly insects and other invertebrates.’
    • ‘Later, become predators and feed on insects, invertebrates, and other small fish.’
    • ‘Gudgeon love feeding upon copepods, tiny shelled invertebrates that form swarms just above the river bed.’
    • ‘Small insects and other invertebrates make up most of the American Redstart's diet.’


  • 1Denoting an invertebrate or relating to the invertebrates as a group.

    • ‘Given the high heritability of sideroxylonal and its effectiveness as a deterrent against vertebrate and invertebrate herbivores, it is surprising that undefended trees persist in the population.’
    • ‘The senior students were keen to observe the invertebrate marine animals, such as starfish, urchins and crustaceans.’
    • ‘The invertebrate ancestors of vertebrates had gill slits, but these were used primarily for filter feeding; these organisms took up most of the oxygen they needed through the skin.’
    • ‘Amphioxus is the closest living invertebrate relative of the vertebrates, and is key to understanding the evolution of vertebrates from an invertebrate ancestor.’
    • ‘Odorant-binding proteins are present in the olfactory systems of both vertebrate and invertebrate animals, but these gene families are not related.’
    • ‘Minerals, mushrooms, higher and lower plants, invertebrate and vertebrate animals make up the richest museum collection on the Balkan Peninsula.’
    • ‘Vertebrate and invertebrate animals, land plants, and protists are all represented as fossils in the Solnhofen Limestone.’
    • ‘While ubiquitous among vertebrates, it occurs less frequently in invertebrate phyla.’
    • ‘The possible role of fibroblast growth factors in organization of the limb blastema is explored and the similarities between vertebrate and invertebrate control of regeneration are discussed.’
    • ‘Echinoderms are considered the invertebrate group most closely related to the vertebrates.’
    • ‘Most endophytes produce N-rich alkaloid compounds that deter or poison a range of vertebrate and invertebrate herbivores.’
    • ‘Once vertebrate and invertebrate eyes were established hundreds of millions of years ago, evolution continued borrowing genes and fine-tuning them for new situations.’
    • ‘Serotonin has been demonstrated to enhance excitability and spike output in vertebrate and invertebrate neurons.’
    • ‘Anhydrobiosis is a state of suspended animation certain invertebrate animals enter in response to severe drought.’
    • ‘Sea cucumbers, invertebrate animals of the phylum Echinodermata, might hold out some hope for the afflicted.’
    • ‘We vertebrates do not stand higher and later than our invertebrate cousins, for all ‘advanced’ animal phyla made their first appearance in the fossil record at essentially the same time.’
    • ‘He then told us that these first life-forms evolved into bacteria and then into the invertebrate animals, as well as plants.’
    • ‘Returning to the United States in 1894, he joined the faculty of the University of California, teaching and carrying out research in both vertebrate and invertebrate paleontology.’
    • ‘Over the last decade, we have become increasingly aware that environmental contaminants act through multiple mechanisms to alter endocrine functioning in vertebrate and invertebrate species.’
    • ‘They are a common adaptation in organisms that use internal fertilization, and have arisen multiple times in a number of vertebrate and invertebrate lineages.’
    1. 1.1humorous Irresolute; spineless.
      ‘so invertebrate is today's Congress regarding foreign policy responsibilities’


Early 19th century (as a noun): from modern Latin invertebrata (plural) the invertebrates (former taxonomic group), from French invertébrés, from in- without + Latin vertebra (see vertebra).