The word 公事 is formed by combining the character 公 (gōng), which conveys the idea of "public", "official", or "collective", with the character 事 (shì), which means "matter", "affair", or "business". The formation is purely conceptual, where the sense of "public/official" from the first character directly modifies and specifies the type of "matter" indicated by the second, resulting in the composite meaning of "official business" or "public affairs". This creates a new, unified concept that is immediately understood as the matters pertaining to an official or public capacity.