The term BALLERINA'S DIGIT is a three letter word for 'TOE'. Ballerinas are professional dancers who specialize in ballet, a type of performance dance that originated in the Italian Renaissance courts of the 15th century. TOE dancing is an important part of ballet, and ballerinas must have strong and flexible toes to perform their intricate steps. Therefore, the term BALLERINA'S DIGIT is a reference to the TOE of a ballerina.