大巴
dà bā · HSK 4
bus
🚌 大 (big) + 巴 (bus, from 巴士 bāshì) = big bus = coach
巴 is the shortened form of 巴士 (bāshì), a Cantonese-origin loan from English 'bus'. Prefixing 大 (big) gives 大巴, the long-distance coach, as opposed to 中巴 (midibus) or 小巴 (minibus).
大 — pictograph of a person with arms outstretched
大 is a pictograph showing a person standing with arms and legs spread wide. The outstretched arms suggest 'big' or 'great', extending from the literal image of a large stance to abstract meanings like important or grand. It is one of the oldest characters, found on oracle bones.
巴 — single pictograph; itself a radical 巴
Traditionally read as a picture of a large snake: the ancient Shuowen dictionary defines 巴 as a snake said to swallow elephants. It also named the ancient Ba state in present-day Chongqing. Today it means 'cling to' or 'long for' (巴不得), and it is a noun suffix in 尾巴 'tail' and 嘴巴 'mouth'.