Why is the ninth month called September?
late 15c., from Middle French excision (14c.) and directly from Latin excisionem (nominative excisio), noun of action from past participle stem of excidere (see excise (v.)).
excision ex·ci·sion (ĭk-sĭzh'ən)n.
Surgical removal by cutting, as of a tumor or a portion of a structure or organ. Also called exsection.
A recombination event in which a genetic element is removed.