'Rupert's ball' definitions:
Definition of 'Rupert's ball'
From: GCIDE
- Rupert's drop \Ru"pert's drop`\ A kind of glass drop with a long tail, made by dropping melted glass into water. It is remarkable for bursting into fragments when the surface is scratched or the tail broken; -- so called from Prince Rupert, nephew of Charles I., by whom they were first brought to England. Called also Rupert's ball, and glass tear. [1913 Webster]