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Pronunciation: yur'a-kus

Definition: That part of the allantois between the apex of the bladder and the umbilicus; postnatally, the urachus is normally merely a fibrous cord, the median umbilical ligament, but occasionally the allantoic lumen may persist as a urachal fistula.

[G. ourachos, the urinary canal of a fetus]

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

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