The word "唠叨" is formed by combining two characters, both featuring the "口" (mouth) radical to indicate relation to speech. "唠" uses the component "劳" primarily for its phonetic sound (láo) while contributing to the sense of incessant or laborious talking, and "叨" similarly uses "刀" for its sound (dāo) while reinforcing the idea of sharp or repeated utterance; together, they redundantly emphasize persistent, annoying talk, thus forming the term meaning to nag or chatter incessantly.