Templates
Templates are used to check that the shape of the pocket openings are correct. They are made as sets of four, two to measure the corner pockets, and two the middle. Of each pair, one measures the width and shape of the top of the cushion and that the pocket doesn't narrow towards the back of the pocket. The other checks the 'fall', and the 'face' of the cushion as it curves inwards - if the 'undercut' is cut too generously it can effectively make the pocket opening wider.
See:-  Face · Fall · Undercut

Tied Frame - Snooker
When the first score or foul on the black at the end of a frame results in the scores being equal, the black is respotted, the cue-ball is played from "hand", and the next score or foul ends the game. In a match consisting of the aggregate score of two or more frames, the black is only respotted if the scores are level at the end of the last frame.

Tips
The circular pieces of leather attached to the shaft of the cue that acts as a cushion between the wooden cue and the cue-ball. Without a tip the cue could not "grip" the cue-ball and no spin (top, bottom or side) could be applied. Miss-cues would be inevitable. Captain François Mingaud is credited with inventing them while imprisoned in a French jail in 1807. He punched them from a leather harness and experimented by shaping them into a rounded dome. It was this apparently simple innovation allowing a more reliable contact between tip and ball that made true control over the cue-ball possible.
See:-  Trick Shots

Top / Top Spin
A form of spin applied to the cue-ball by striking it above centre and following through with the cue. This forward spin accelerates the cue-ball after its contact with the object-ball.
See:-  Follow · Follow-Through

Top of the Table
The end of the table at which, in snooker, the black is spotted.
See:-  Bottom of the Table

Top of the Table Game - English Billiards
Refers to two specific types of break building in which the three balls remain within the top half of the table.
See:-  Floating White · Postman's Knock

Top Pockets
The two corner pockets in the top half of the table.
See:-  Bottom Pockets · Pockets

Touching Balls
Applies to one or more balls that are touching. If one of them is the cue-ball then play must continue according to the rules of the particular game being played:

English Billiards Snooker

- A B C D

The balls are respotted - the red is placed on the Spot, the object-white on the Centre Spot, and the striker continues in play from the 'D'. The striker must play away from the ball without moving it. If the player is on a red, and the cue-ball is touching a red, then the cue-ball can be played away - with or without making contact on any other ball - and it is deemed a fair stroke. If the player is on a red, and the cue-ball is touching a colour, then the cue-ball must be played away and must contact a red for it to be deemed a fair stroke. If the player is on a colour, and the cue-ball is touching a colour, the player may nominate the colour touching the cue-ball as the ball he is "on", and then play away - with or without making contact on any other ball - and it is deemed a fair stroke. If any other colour is nominated as the ball "on" then that ball must be struck by the cue-ball.

Trick Shots
Although trick shots have been played for centuries the first true exponent was Francois Mingaud whose "Noble Jeu de Billard" was published in Paris in 1827. He toured Europe giving exhibitions and some of his shots would be considered extraordinary even by today's top players. The shot shown in the animation is one of his, and while many of today's professionals have included it in their exhibitions, it's doubtful if they know just how old the shot is, or if they gave Mingaud the credit he was due. More information on Mingaud's shots (and many others) can be found in Robert Byrne's "Treasury of Trick Shots in Pool & Billiards"

Twisting Chalk
The name John Carr gave to the "special" chalk that he claimed was responsible for his 'wonderful powers' in about 1820. He was one of the earliest exponents of side and screw.

Undercut
Refers to the cutting back of the bottom of the rubber at the face of the cushion as it curves to form the pocket opening. This raises the contact point above the centre of the ball and effectively widens the pocket.
See:-  Face · Cushions · Pockets · Templates

Volunteer Snooker
A variation that allowed a player, after potting a red and colour, to 'volunteer' to play again on a nominated colour. There was no limit to the number of volunteered colours the player could pot, although if the same one was potted three times in succession from the same spot it then remained off the table until the next stroke had been played. If a player failed to pot a volunteered colour then it was deemed a foul stroke. Volunteer Snooker appeared in the official rule book for over thirty years.
See:-  Snooker · Snooker Plus

Whitechapel - English Billiards
A derogatory term describing the deliberate potting of the opponent's cue-ball.

Winning Hazard
The original term for a pot.
See:-  Losing Hazard

X
Not a darned thing !
See:-  Z

Yellow Spot - Snooker
The right-hand spot of the baulk-line on which the yellow is spotted.
See:-   Baulk Spots · Right-Hand Spot of the 'D' · Spots

Z
Same as X !