adj. Of or relating to aviation: a flying time of three hours between cities. adj. Capable of or engaged in flight: The bat is a flying mammal. adj. Situated, extending, or functioning in the air: a flying deck. adj. Swiftly moving; fleet: played the difficult passage with flying fingers. adj. Done or performed swiftly in or as if in the air: crossed the goal line with a flying leap. adj. Brief; hurried: made a flying visit to the neighbors' house; took a flying glance at the report. adj. Capable of swift deployment or response; extremely mobile.adj. Nautical Not secured by spars or stays. Used of a sail.n. Flight in an aircraft or spacecraft.n. The piloting or navigation of an aircraft or spacecraft.idiom. with flying colors With complete or outstanding success: passed the Latin examination with flying colors.