突破口
tupòkǒu · HSK 7
breach
🕳️ 突 burst + 破 break + 口 opening = the opening you burst and break through
破 — stone 石 + skin/hide 皮
破 is a semantic-phonetic compound: 石 (stone) gives the meaning 'to break, smash,' since stones were used to crack things, while 皮 (pí) supplies the sound. The original sense of breaking stone broadened to mean 'broken,' 'damaged,' or 'to defeat.'
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.