The word "卜卦" is formed by combining the character "卜", meaning to divine or prophesy, with the character "卦", meaning a divinatory hexagram or symbol. Together, they create a compound term where "卜" denotes the act of divination and "卦" specifies the use of hexagrams, typically from systems like the I Ching, resulting in a word that directly refers to the practice of casting hexagrams for fortune-telling.