[ ɪn'və:tɪbrət ]
■ noun an animal lacking a backbone, such as an arthropod, mollusc, annelid, etc. Compare with vertebrate .
■ adjective relating to the ~s.
Origin
C19: from mod. L. invertebrata (plural) (former taxonomic group), from Fr. invertébrés , from in- 'without' + L. vertebra (see vertebra ).