The word "drift" means to be carried along by wind, water, or any other force without control or purpose. It can also refer to a gradual change or shift in something's position, direction, or meaning. Full definition
After forty days of drifting in the sea, they suddenly become prisoners of war. (nerdlocker.com)
Both have a knack of drifting into dangerous areas inside the penalty area, cutting in from the flank. (footballwhispers.com)
Taking my eyes off of the road to adjust the radio can result in drifting into other lane, even if just for a second; no feel of the road here. (carsdesk.com)