The term 'letter on a dreidel' refers to the four Hebrew letters that are inscribed on the sides of a traditional dreidel. These letters are SHIN (ש), NUN (נ), Gimel (ג), and Hei (ה). SHIN stands for the Hebrew word 'SHIN, ' which means 'PUT, ' NUN stands for the Hebrew word 'NUN, ' which means 'TAKE, ' Gimel stands for the Hebrew word 'gimel, ' which means 'all, ' and Hei stands for the Hebrew word 'hei, ' which means 'HALF.' Together, these four letters form the acronym 'Nes Gadol Hayah Sham, ' which means 'a great miracle happened there.'