This article is from the Pool & Billiards FAQ, by Bob Jewett with numerous contributions by others.
Ball in hand
The freedom to place the ball anywhere on the table, or sometimes
in a restricted area
Baulk Cushion
The end rail farthest from where you rack (British). Also called
the "bottom" cushion.
Break
At pool, the first shot of a game, often a smash shot which is
called an "open break". On an English table, a succession of
scoring shots that would be called a "run" in the US.
Cut shot
A shot in which the object ball is driven other than straight
ahead. The difference between straight and the angle the object
ball takes is called the cut angle.
Double
Bank shot (British)
Drag shot
A draw shot played slowly enough that the back spin has turned
into follow by the time the cue ball gets to the object ball.
The goal is to reduce cue ball movement after contact but to
avoid "slow rolling" the cue ball, which may roll off if the
table isn't level.
Draw
Back spin on the cue ball, and the opposite of follow. It
generally makes the cue ball come back towards you after
contact with an object ball. See below for how to do it.
End rail
The two shorter cushions at each end of the table.
English
Spin on the cue ball, especially side spin ("side" in the UK)
Ferrule
That little white thingy just behind the cuetip :-) In the UK,
they use brass for ferrules.
Follow
Topspin on the cue ball. It comes from friction with the
cloth (natural roll) or from hitting the cue ball above
center. It generally carries the the cue ball forward after
contact with an object ball.
Foot spot
A point marked on the cloth two diamonds from the foot rail (the end
rail where the balls are racked on a pool table), on the center line
of the table.
Foul
An infraction of the rules that generally ends a player's inning
(though it is possible to foul when not shooting).
Head spot
A point two diamonds from the head rail on a pool table (the end
rail that you break from), in the center of the table. It's the
center of the head string.
Inning
A turn at the table, usually ending in a miss, foul or win.
In The Kitchen
Same as "ball in hand" but requires the cue ball to be behind
the head string.
Inside english
If you play a cut shot, and the object ball goes to your right,
right english would be inside english. Similarly for a left cut
with left english. Inside/outside pertaining to english has nothing
to do with the location of the cushion on the shot, only with the cut
angle and the side of english. You can remember which is inside by
the location of the stick relative to the the "body" of the shot.
Kick
At snooker and English billiards, the action you get when the cue
ball sticks to the object ball for an instant. The most likely
explanation is that it is from dirt, and especially chalk, between
the balls at the instant of impact.
Kick shot
At pool, a shot where the cue ball hits a rail first, commonly as
a return of safety.
Kitchen
Area behind the head string.
Lagging
A way to determine who shoots first. Each player puts a ball behind
the head string and banks it off the foot rail. The player whose
ball stops closer to the head rail has choice of shooting first or
second. ("Stringing" in the U.K.)
Masse
A shot with the stick nearly vertical to make the cue ball
curve (with side spin) or reverse direction (with back spin)
or both. Less elevation is called "half-masse" which grades
down into "swerve" (see below). (moss-say or mass-say)
Outside english
The opposite of inside english (see above). On a cut to the left,
it is right english.
Pot
To pocket a ball without a foul (British)
Reverse english
Side spin on the ball that tends to make it go slower when
it contacts a cushion. (check side in the UK) Also called
hold-up.
Running english
Side spin on the ball that tends to make it go faster when it
contacts a cushion. (running side in the UK)
Safety
A shot intended to leave nothing for the opponent
Scratch
Cue ball into a pocket, off the table, or sometimes any foul
Screw
Back spin in the UK ("draw" in the US)
Skid
Also called cling. The US term for "kick" -- see above.
Squirt
A cue ball hit with side spin does not start out parallel to the axis
of the cue stick, but instead moves slightly away from that by an
angle up to four degrees, depending on the stick and the spin. No one
understands exactly why this happens, but it seems to go up with the
amount of mass in the front six inches of the stick. See Ron Shepard's
paper at http://www.sfbilliards.com/Shepard_squirt.pdf for current
theory. It is also called "deflection", but since there are many
different deflections in pool and billiards, and because this
phenomenon is critical to playing well with side spin, it gets its own
name.
Stop/Stun Shot
A stop shot is when the cue ball hits the object ball full and has
no follow or draw, so it stops completely upon contact. If there
is an angle, it is called a stun shot, and the cue ball will travel
at (close to) a right angle to the path of the object ball.
Swerve
A cue ball hit with side spin and an (even slightly) elevated cue
stick will curve in the direction of the applied English. Elevate
more and it's masse. You elevate on nearly all shots, whether you
intend to or not.
Throw
The divergence of an object ball from the line through the
centers of it and the impacting ball. Throw is induced by the
friction between the two balls and the relative motion of
their surfaces. [Note: in UK usage, "throw" is synonymous
with "squirt", and has nothing to do with friction between two
balls.]
On-line pool jargon is available at http://www.onthesnap.com/jargon.htm
and at http://www.sfbilliards.com/jargon.html
 
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