Definitions for "Bi-metallic"
A coin comprised of two sepatate pieces of metal. Normally one metal is used as a centerpiece ( core) with the second metal surrounding ( annulus) it to form two concentric circles.
A coin made of 2 different metals. For example the current UK Two Pound coin, or the 1 and 2 Euro Coins.
a coin comprised of two different metals, bonded together.