上 + Son
Meaning
Here 上 does not carry its usual sense of “on” or “up”. Placed before a number, it says the quantity has reached or passed a certain order of magnitude: “over”, “as many as”.
Basic structure
上 + Number + Measure word → over…
Examples
这个城市的地铁已经有上百年的历史了
每年有成千上万的高中毕业生参加艺术考试
爱迪生就是在找了上千种材料后才找到了能点亮电灯的材料
Common forms
上百 — over a hundred 上千 — over a thousand 上万 — over ten thousand 上百万 — millions 成千上万 — tens of thousands, countless
有上千人参加
这本书卖了上百万册
公司有上万人
上百 vs. 一百多
一百多人 — a little over a hundred (roughly 101–199). 上百人 — has reached the hundred mark; no upper limit implied. 几百人 — several hundred people.
Remember:
Here 上 means “has reached the next order”.
上百 → into the hundreds, 上千 → into the thousands, 上万 → into the tens of thousands.
It has nothing to do with 上 meaning “on top”.