Back Bilyard şarı Azerbaijani Bola de billar Catalan Bal (billard) Danish Billardkugel German Bola de billar Spanish توپ بیلیارد Persian Boule de billard French Bola biliar ID ビリヤードボール Japanese 당구공 Korean
- Russian pyramid and kaisa—68 mm (2+11⁄16 in)
- Carom—61.5 mm (2+7⁄16 in)
- International pool—57.15 mm (2+1⁄4 in)
- Snooker—52.5 mm (2+1⁄16 in)
- British-style pool—51 mm (2 in)
A billiard ball is a small, hard ball used in cue sports, such as carom billiards, pool, and snooker. The number, type, diameter, color, and pattern of the balls differ depending upon the specific game being played. Various particular ball properties such as hardness, friction coefficient, and resilience are important to accuracy.