势头
shì toú · HSK 7
momentum
势 force/momentum + 头 head = the leading head of a force, i.e. momentum
势 carries the sense of force or power; 头 means head or front end. Together they name the forward push of something already moving, so 势头 covers momentum, impetus, and which way a trend is heading.
头 — 页 (head/page) + 豆 (bean, phonetic)
The traditional form 頭 combines 頁 (xié), meaning 'head', with 豆 (dòu) as the phonetic component. 頁 itself originally depicted a person with an emphasized head. The simplified form 头 is a modern shorthand that replaces 豆+頁 with a simpler shape while keeping the same meaning of 'head' or 'top'.