umbilicus
/ʌmˈbɪlɪkəs/noun
(pl. umbilici /-saɪ/ 或umbilicuses)
1- Anatomy the navel【解剖】脐。
1.1
- Zoology a depression or hole at the centre of the shell whorls of some gastropod molluscs and many ammonites【动】（贝壳的）脐。
1.2
- Zoology a hole at each end of the hollow shaft of a feather【动】翮孔。
词源
late 17th cent.: from Latin: related to Greek omphalos, also to NAVEL.