特快
tè kuài · HSK 6
express
🚄 特 (special) + 快 (fast) = specially fast, i.e. express
Think of it as the extra-fast option. 特 means special or extra, 快 means fast. Together they label anything that moves faster than standard: express trains, express delivery, express lanes.
特 — cow 牛 + temple 寺 (phonetic)
Originally referred to a male bull or large ox, with 牛 'cow' as the meaning component and 寺 supplying the sound. Over time it shifted from 'bull' to 'special, particular, unique,' the sense used today.
快 — heart radical 忄 + 夬 (phonetic)
快 is a semantic-phonetic compound. The heart radical 忄 carries the meaning, since the original sense referred to a feeling of pleasure or delight. The right side 夬 supplies the sound. The meaning later extended from 'pleased' to 'quick, fast', the dominant modern sense.