invertebrate Meaning, Definition & Usage

  1. noun any animal lacking a backbone or notochord; the term is not used as a scientific classification
  2. adjective lacking a backbone or spinal column
    spineless.
    • worms are an example of invertebrate animals

WordNet

In*ver"te*brate adjective
Definitions
  1. (Zoöl.) Destitute of a backbone; having no vertebræ; of or pertaining to the Invertebrata. -- n. One of the Invertebrata.

Webster 1913