SEPT, a clan, the term generally applied to the tribes or families of Ireland, used also sometimes as by Sir H. Maine (Early History of Institutions, 231) of the Indian joint undivided family, the " combined descendants of an ancestor long since dead." Wedgewood (Diet, of Eng. Etym.), quoted by Skeat, takes the word as a corruption of " sect " (q.v.), and cites from the State Papers of 1536 and 1537, where secte and seple are used respectively. If so, the word must have been influenced by Lat. saeplum, fence or enclosure (saepire, to enclose, saepes, hedge), a word which has been adopted as " septum " into scientific terminology for any partition or wall dividing two cavities e.g. in anatomy, of the partition between the nostrils, septum naris, or that between the right and left ventricles of the heart, septum cordis.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)