The compound word "大致" is formed through the combination of two characters: "大" (dà), meaning "big" or "great", and "致" (zhì), which in this context conveys the sense of "to reach", "to result in", or "extent". Together, they create a semantic union where "大" modifies the scope implied by "致", yielding the meaning of "to a great extent" or "the main aspect". This logically evolved into its modern adverbial and adjectival senses of "roughly", "generally", or "approximate", describing something that covers the main points without fine detail. Thus, its formation exemplifies how Chinese compounds often synthesize abstract conceptual relationships from concrete character meanings.