The Oxford Thesaurus An A-Z Dictionary of Synonyms - excursion n.

1) trip, tour, outing, airing, expedition, voyage, cruise, journey, junket, jaunt; ramble, stroll, walk, hike, trek, drive, ride, sail: We left the city and took an excursion into the mountains. 2) detour, deviation, side-trip, diversion, digression, excursus: Forgive the excursion, but I'll return to the subject in a minute.