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Pronunciation: is'mus, -mi, -mus-ez

Definition: A constriction in the embryonic neural tube delineating the anterior portion of the rhombencephalon, the future metencephalon, from the more rostrally located mesenephalon.

Synonym(s): rhombencephalic isthmus

[G. isthmos]

Further information

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.