The word "公章" is formed by combining the character "公", meaning public or official, which itself is composed of the components "八" (representing division) and "厶" (representing private), with the character "章", meaning seal or stamp, composed of "音" (sound) and "十" (ten), historically referring to a musical movement but later extended to mean a seal. Together, "公章" literally denotes an official seal, where "公" modifies "章" to specify its public or official nature.