The compound word "心术" is formed through semantic combination, where "心" (xīn) means "heart" or "mind," representing one's inner thoughts and intentions, and "术" (shù) means "method," "art," or "technique." Together, they create an abstract concept that metaphorically refers to the "methods of the heart/mind"—that is, the underlying strategies, intentions, or moral character guiding a person's actions and thoughts. It does not describe a physical technique but rather the inner workings and ethical quality of one's mind, often carrying a nuance of calculation or one's true, often hidden, motives.