1550s, "act or fact of crossing," from Middle French intersection (14c.) and directly from Latin intersectionem (nominative intersectio) "a cutting asunder, intersection," noun of action from past participle stem of intersecare "intersect, cut asunder," from inter- "between" (see inter-) + secare "to cut" (from PIE root *sek- "to cut"). In English originally a term in geometry; meaning "crossroads, a place of crossing" is from 1864. Related: Intersectional.
