noun

a journey undertaken by a group of people with a particular purpose, especially that of exploration, research, or war.

an expedition to the jungles of the Orinoco

journey,voyage,tour,odyssey,undertaking,enterprise,mission,project,quest,operation,commission,assignment,exploit,exploration,safari,trek,hike,survey,peregrination,trip,excursion,outing,jaunt,run,junket,hop