This is typically a billiards term meaning, "a shot in billiards in which the cue ball strikes each of two object ball".
Two. There are two white and one red ball used for billiards.
15 ADD: Completely incorrect. This answer refers to pocket billiards, and more specifically "8 ball" or "boston" or "stripes and solids". In billiards, there are three balls. One of one color, and two of another.
The 2 Ball Billiards has but 3 balls, white, spot white & red. The blue is worth 5 in snooker.
There are none in English Billiards. In Carom Billiards, there are none. In the Pocket Billiards games, the 8 ball is the only black ball - 7 Ball has no 8 ball, hence no black ball, but all other games include the 8 ball, so, they have 1 black ball.
For pocket billiards, 9 ball is often won in 1 shot. Both 8 ball and 9 ball can be won on the break,
The English Billiards balls are either white or red.
Cue Ball
who invented eight ball billiards
Pool, billiards, croquet, boccie ball, dodge ball (depending on the house rules), team golf,
In the US, a billiards ball or pool ball is 2.25 inches in diameter. This is 1.125 for its radius. The only exception is the oversize cue ball, which is 2.375 inches in diameter.
Red.