The word "搔痒" is formed by combining the character "搔", meaning to scratch, which incorporates the hand radical "扌" to indicate a manual action and the component "蚤" suggesting irritation, with the character "痒", meaning itch, which uses the sickness radical "疒" to denote physical discomfort and the component "羊" primarily for phonetic value. Together, they create a compound where the first character specifies the action and the second specifies the condition, directly conveying the act of scratching an itch.