1. on the run or in a hurry
; - Example: "she wrote those letters on the fly"
The Collaborative International Dictionary of English v.0.48:
Fly \Fly\, n.; pl. Flies (fl[imac]z). [OE. flie, flege, AS.
fl[=y]ge, fle['o]ge, fr. fle['o]gan to fly; akin to D. vlieg,
OHG. flioga, G. fliege, Icel. & Sw. fluga, Dan. flue. [root]
84. See Fly, v. i.]
(a) Any winged insect; esp., one with transparent wings;
as, the Spanish fly; firefly; gall fly; dragon fly.
(b) Any dipterous insect; as, the house fly; flesh fly;
black fly. See Diptera, and Illust. in Append.
2. A hook dressed in imitation of a fly, -- used for fishing.
"The fur-wrought fly." --Gay.
3. A familiar spirit; a witch's attendant. [Obs.]
A trifling fly, none of your great familiars. --B.
4. A parasite. [Obs.] --Massinger.
5. A kind of light carriage for rapid transit, plying for
hire and usually drawn by one horse. [Eng.]
6. The length of an extended flag from its staff; sometimes,
the length from the "union" to the extreme end.
7. The part of a vane pointing the direction from which the
8. (Naut.) That part of a compass on which the points are
marked; the compass card. --Totten.
(a) Two or more vanes set on a revolving axis, to act as a
fanner, or to equalize or impede the motion of
machinery by the resistance of the air, as in the
striking part of a clock.
(b) A heavy wheel, or cross arms with weights at the ends
on a revolving axis, to regulate or equalize the
motion of machinery by means of its inertia, where the
power communicated, or the resistance to be overcome,
is variable, as in the steam engine or the coining
press. See Fly wheel (below).
10. (Knitting Machine) The piece hinged to the needle, which
holds the engaged loop in position while the needle is
penetrating another loop; a latch. --Knight.
11. The pair of arms revolving around the bobbin, in a
spinning wheel or spinning frame, to twist the yarn.
12. (Weaving) A shuttle driven through the shed by a blow or
(a) Formerly, the person who took the printed sheets from
(b) A vibrating frame with fingers, attached to a power
to a power printing press for doing the same work.
14. The outer canvas of a tent with double top, usually drawn
over the ridgepole, but so extended as to touch the roof
of the tent at no other place.
15. One of the upper screens of a stage in a theater.
16. The fore flap of a bootee; also, a lap on trousers,
overcoats, etc., to conceal a row of buttons.
17. (Baseball) A batted ball that flies to a considerable
distance, usually high in the air; also, the flight of a
ball so struck; as, it was caught on the fly. Also called
fly ball. "a fly deep into right field"
[1913 Webster +PJC]
18. (Cotton Manuf.) Waste cotton.
[Webster 1913 Suppl.]
Black fly, Cheese fly, Dragon fly, etc. See under
Black, Cheese, etc. -- Fly agaric (Bot.), a mushroom
(Agaricus muscarius), having a narcotic juice which, in
sufficient quantities, is poisonous. -- Fly block
(Naut.), a pulley whose position shifts to suit the
working of the tackle with which it is connected; -- used
in the hoisting tackle of yards. -- Fly board (Printing
Press), the board on which printed sheets are deposited by
the fly. -- Fly book, a case in the form of a book for
anglers' flies. --Kingsley.Fly cap, a cap with wings,
formerly worn by women. -- Fly drill, a drill having a
reciprocating motion controlled by a fly wheel, the
driving power being applied by the hand through a cord
winding in reverse directions upon the spindle as it
rotates backward and forward. --Knight.Fly fishing, the
act or art of angling with a bait of natural or artificial
flies; fishing using a fly as bait. --Walton. -- --
Fly fisherman, one who fishes using natural or artificial
flies as bait, especially one who fishes exclusively in
that manner. -- Fly flap, an implement for killing
flies. -- Fly governor, a governor for regulating the
speed of an engine, etc., by the resistance of vanes
revolving in the air. -- Fly honeysuckle (Bot.), a plant
of the honeysuckle genus (Lonicera), having a bushy stem
and the flowers in pairs, as L. ciliata and L.
Xylosteum. -- Fly hook, a fishhook supplied with an
artificial fly. -- Fly leaf, an unprinted leaf at the
beginning or end of a book, circular, programme, etc. --
Fly maggot, a maggot bred from the egg of a fly. --Ray.
Fly net, a screen to exclude insects.
Fly nut (Mach.), a nut with wings; a thumb nut; a finger
Fly orchis (Bot.), a plant (Ophrys muscifera), whose
flowers resemble flies.
Fly paper, poisoned or sticky paper for killing flies that
feed upon or are entangled by it.
Fly powder, an arsenical powder used to poison flies.
Fly press, a screw press for punching, embossing, etc.,
operated by hand and having a heavy fly.
Fly rail, a bracket which turns out to support the hinged
leaf of a table.
Fly rod, a light fishing rod used in angling with a fly.
Fly sheet, a small loose advertising sheet; a handbill.
Fly snapper (Zool.), an American bird (Phainopepla
nitens), allied to the chatterers and shrikes. The male
is glossy blue-black; the female brownish gray.
Fly wheel (Mach.), a heavy wheel attached to machinery to
equalize the movement (opposing any sudden acceleration by
its inertia and any retardation by its momentum), and to
accumulate or give out energy for a variable or
intermitting resistance. See Fly, n., 9.
On the fly (Baseball), still in the air; -- said of a
batted ball caught before touching the ground..
WordNet (r) 3.0 (2006):
on the fly
adv 1: on the run or in a hurry; "she wrote those letters on the