The word "喑哑" is formed by combining two characters, each containing the "口" (mouth) radical to indicate relation to speech or sound. "喑" integrates the phonetic component "音" (sound) to suggest pronunciation and associate with silence or muteness, while "哑" uses the phonetic component "亚" to suggest pronunciation and associate with hoarseness or muteness. Together, they create a compound word where both characters semantically and phonetically contribute to the meaning of being mute or voiceless.