The word "皎洁" is formed by combining the character "皎", which is a phono-semantic compound with the semantic radical "白" (white) indicating brightness and the phonetic component "交" suggesting pronunciation, and the character "洁", a simplified form derived from "潔" with the semantic radical "氵" (water) indicating cleanliness and the phonetic component "吉" suggesting sound in its simplified form; together they create a compound word meaning bright and clean, typically used to describe moonlight.