Quiz: Remember the definition of mal de mer?
small, smooth stone, late 13c., from Old English papolstan "pebblestone," of unknown origin. Perhaps imitative. Some sources compare Latin papula "pustule, pimple, swelling."
A polymorphic language.
["A Kernel Language for Abstract Data Types and Modules", R.M. Burstall & B. Lampson, in Semantics of Data Types, LNCS 173, Springer 1984].