do something on the fly Definition

fly²
verb flies (3rd person present tense), flew (past tense), flown (past participle), flying (present participle)

intr
1a. Said of birds, bats, insects and certain other animals: to move through the air using wings or structures resembling wings;

Thesaurus: soar, wing, float, glide, hover, sail, flit, flutter, take wing.
intr
1b. Said of an aircraft or spacecraft: to travel through the air or through space.
tr & intr
2. To travel or convey in an aircraft.

Example: They flew to Moscow
Example: The company flew them to Moscow
3. To operate and control (an aircraft, kite, etc); to cause it to fly.

Example: The pilot flew the plane competently
Thesaurus: pilot, navigate, aviate, jet, manoeuvre.
4. To cross (an area of land or water) in an aircraft.

Example: They flew the Atlantic to New York
5a. To raise (a flag);

Example: fly the flag on St George's day
intr
5b. Said of a flag: to blow or flutter in the wind.
intr
6. To move or pass rapidly.

Example: fly into a temper
Example: rumours flying around
Thesaurus: speed, rush, sprint, tear, dart, scoot.
intr
7. colloq
To depart quickly; to dash off.
Example: I must fly
Thesaurus: bolt, take to one's heels, vamoose (US slang), hightail it (US slang), clear out.
tr & intr
8. To escape; to flee (a country, a war zone, etc).

Thesaurus: escape, retreat, abscond, get away, withdraw, disappear, run for it.

noun flies

1. A zip or set of buttons fastening a trouser front, or the flap covering these.

Form: flies (chiefly)
2. A flap covering the entrance to a tent.
3. The space above a stage, concealed from the audience's view, from which scenery is lowered.

Form: flies
4. Short for flywheel.

Idiom: do something on the fly

To work something out immediately without any preparation.

Idiom: fly by the seat of one's pants

To do a job instinctively or by feel when one doesn't know the usual procedure.

Idiom: fly high

To be ambitious.

To prosper or flourish.

Idiom: fly in the face of something

To oppose it; to be at variance with it.
Thesaurus: defy, rebel against, disobey.

Idiom: fly a kite

To release information about an idea, proposal, etc to find out what people's opinion might be about it.

Idiom: fly off the handle

To lose one's temper.

Idiom: fly open

Said of a door, window, etc: to open suddenly or violently, due to a gust of wind, someone's abrupt entry, etc.

Idiom: let fly

To loose one's temper (with someone).
Example: Suddenly, Paul let fly at Mark

Idiom: let something fly

To shoot or throw something.

Idiom: send someone or something flying

To knock them down or knock them over with considerable force.

Etymology: Anglo-Saxon fleogan.

Phrasal Verb: fly at or out at someone

To attack them angrily and suddenly.