umbilical cord

noun

(Anatomy) The flexible cordlike structure connecting a fetus at the abdomen with the placenta and containing two umbilical arteries and one vein that transport nourishment to the fetus and remove its wastes
something likened to an umbilical cord; a source or means of support or sustenance
a tethering or supply line (as for an astronaut outside a spacecraft or a diver underwater)
any of various external electrical lines or fluid tubes that supply a rocket before launch
extra-embryonic structure