septum (n.)youdaoicibaDictYouDict[septum 词源字典]
"partition between the nostrils," 1690s, Modern Latin, from Latin saeptum "a fence, enclosure, partition," from neuter past participle of saepire "to hedge in," from saepes "hedge, fence." Related: Septal.[septum etymology, septum origin, 英语词源]
transept (n.)youdaoicibaDictYouDict
"transverse section of a cruciform church," 1530s, from Medieval Latin transeptum, from Latin trans- "across" (see trans-) + saeptum "fence, partition, enclosure" (see septum). Rare before 1700. Related: Transeptal.