The term 'minor piece' is primarily used in chess to describe the bishop and knight. However, there are other synonyms one can use when referring to these pieces. The bishop is often called the 'light' or 'dark-squared bishop' depending on the color of the square it starts on. It can also be known as the 'diagonal piece' due to its unique movement pattern. The knight, on the other hand, can be called the 'horse' due to its shape or the 'jumper' due to its ability to leap over other pieces. Additionally, the combination of these two pieces is sometimes referred to as the 'minor pieces' or 'minor parts' of a chess army.