"pertaining to the navel," 1540s, from M.L. umbilicalis "of the navel," from L. umbilicus "navel," from PIE *onobh- (source of Gk. omphalos and related to *nobh, source of navel). First record of umbilical cord is from 1753. Umbilicus for "navel" is attested from 1690s but mostly is confined to medical writing.