British silver coin with a face value of 4d(1.66p). Its name derives from the word 'great', because of the coin's size compared with the smaller penny. Groats were mainly used 1350-1560, but were issued before and after these dates. The Britannia groat, for example, was issued in the 19thC. This was the same size as the silver 3d but thicker and displayed the face of Britannia.