悪口
わるくち · warukuchi · JLPT N3 · noun
maltreatment
👄 悪口 = bad (warui) + mouth (kuchi): a bad mouth, so insults
悪 (waru-) is the stem of warui, meaning bad, and 口 (kuchi) means mouth. In English, to bad-mouth someone means to insult them, and Japanese builds the word the same way: 悪口を言う means to speak ill of someone.
口 — pictograph of an open mouth
口 is one of the oldest pictographs in Chinese, originally drawn as a simple outline of an open mouth. Its core meaning 'mouth' extended naturally to 'opening' or 'entrance', as in 入口 (entrance). It also serves as a common radical in characters related to speech, eating, or apertures.