The word "讪笑" is formed by combining the character "讪", meaning to mock or ridicule, which incorporates the speech radical "讠" to indicate verbal action along with the component "山" primarily for phonetic indication, and the character "笑", meaning to laugh, which uses the bamboo radical "竹" and the component "夭" for both phonetic and semantic contributions. Together, these characters create a compound word that specifically denotes laughing at someone in a mocking or scornful manner.