Definition of somite in English:



  • Each of a number of body segments containing the same internal structures, clearly visible in invertebrates such as earthworms but also present in the embryonic stages of vertebrates.

    Also called metamere
    • ‘This takes the vertebrate embryo up to the stage at which it has become recognizably vertebrate, with somites, notochord, and neural tube.’
    • ‘The trunk section, the perion, consists of the remainder of the typical thoracic somites.’
    • ‘The neural tube of the body tends to segment in an orderly way along the boundaries between somites.’
    • ‘If male abdomina are preserved, the fusion of the somites is also diagnostic; pseudoziids exhibit no fusion of somites while carpiliids have somites 3-5 fused.’
    • ‘The basis for the confusion arises from the visible suture between somites 4 and 5, which suggests that the fusion is not complete.’


Mid 19th century: from Greek sōma body + -ite.