bonzoline|ˈbɒnzəliːn| A composition used as a substitute for ivory in the manufacture of billiard balls. 1896Daily News 18 Apr. 6/1 During the last two or three years the balls have been made of a new composition called bonzoline.1899Westm.Gaz. 10 Nov. 5/2 Bonzoline billiard balls.