The crossword solution for the term MOTIVE STARTER is LOCO, which is a four-letter word. LOCO is a Spanish word meaning 'CRAZY' or 'INSANE'. It is often used to describe someone who is acting in an irrational or unpredictable manner. In this context, it can be used to refer to something that serves as a catalyst for a particular action or behavior. Thus, LOCO can be used to describe a MOTIVE STARTER, or something that initiates a particular course of action.