primitive streak

noun
|Updated on: 27 May 2018

Definition of primitive streak

: an elongated band of cells that forms along the axis of a developing fertilized egg early in gastrulation and that is considered a forerunner of the neural tube and nervous system

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First Known Use of primitive streak

1833

in the meaning defined above

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Medical Dictionary

primitive streak

noun

medical Definition of primitive streak

: an elongated band of cells that forms along the axis of an embryo early in gastrulation by the movement of lateral cells toward the axis and that develops a groove along its midline through which cells move to the interior of the embryo to form the mesoderm

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