The term 'BULL' can be broken down into two crossword solutions: PREF. and TAUR (4 letters) and TAURO (5 letters). PREF. stands for prefix, which is a word or group of letters added to the beginning of a word to change its meaning. TAUR and TAURO are both derived from the Latin word taurus, which means BULL. The term 'BULL' is often used to refer to a large, strong animal, such as a cow or ox. It can also be used to describe someone who is aggressive or intimidating.