(intransitive, baseball) To hit a fly ball; to hit a fly ball that is caught for an out. Compare ground (verb) and line (verb).

(baseball, of the ball) While in the air, without having touched the ground. / (idiomatic) Spontaneously or extemporaneously; done as one goes, or during another activity.

(aviation) An informal gathering of private pilots and their aircraft at a prearranged airfield.

(of airspace) In which aircraft are forbidden to fly. / (of people) Who are forbidden to board an aircraft.

Used other than figuratively or idiomatically: see fly, by. / (idiomatic) To pass or go past quickly, often without much interaction

Alternative spelling of on the fly

plural of fly (a type of carriage) / plural of fly (butterfly stroke)

A surname.

plural of Fly

Alternative form of flyby