The careful going-and-looking-again — study that returns with sources, never with guesses.
Old French recerchier: re- (again) + cerchier (to search), from Latin circare (to go around), from circus (a circle); research is, at its root, a careful going-around and back again, not a single pass.
The careful going-and-looking-again — study that returns with sources, never with guesses. The root's repeated circling is the discipline itself: one look is a glance, and research is what happens after several.