Glossary of Cue Sports Terms - U

U

umbrella shot

A three cushion billiards shot in which the cue ball first strikes two cushions before hitting the first object ball then hits a third cushion before hitting the second object ball. So called because the shot opens up like an umbrella after hitting the third rail. Umbrella shots may be classified as inside or outside depending on which side of the first object ball the cue ball contacts.

umpire

Chiefly American, and largely obsolete: Same as referee. Derives from the usage in baseball.

undercut

Also under-cut.

1 To hit the object ball with not enough of a cut angle; hitting the object ball too full or "fat". It is a well-known maxim that overcutting is preferable to undercutting because of the principle of the "professional side of the pocket". May be used as a noun: "That was a bad undercut."

2. On snooker and English billiards tables, to trim back (usually by filing and sanding, not actually cutting) the underside of the protruding knuckle of the cushion, a.k.a. the nose of the cushion, from where the cushion starts to curve into the pocket until it ends inside the pocket jaws. The result is a cushion face at the knuckle that angles inward toward where the base of the rail meets the bed of the table, instead of one that is perpendicular to the bed. At this point it is thus more like a triangular pool cushion profile, with its "backboard" effect, than a sideways-L-shaped snooker cushion profile. Undercut knuckles make for an easier pocket to pot balls in from an angle – a "faster pocket speed" – because they raise the contact point between cushion and ball to above the centre of the ball, reducing the tendency of the ball to be rebounded away. Also used as a noun: "The amount of the undercut has a major effect on pocket playability."

unders

Same as solids, in New Zealand. Compare little, small, reds, low, spots, dots; contrast overs.

unintentional english

Inadvertent english placed on the cueball by a failure to hit it dead center on its horizontal axis. It is both a common source of missed shots and commonly overlooked when attempts are made to determine the reason for a miss. In UK parlance this is usually called 'unwanted side'.

up-table

Toward the head of the table.