足 Radical 157 — foot, leg; enough, sufficient
zú (second tone, rising)
foot, leg; enough, sufficient
Radical 1577 strokes2 characters
Also written ⻊ — the same radical in a different position inside the character.
Where the shape comes from
The whole leg from the knee down: the box at the top is the kneecap and the shape below it is 止, the footprint. On the left of a character it is squeezed into ⻊, and there it marks every way a leg can be used: 跑 to run, 跳 to jump, 踢 to kick, 路 a road, 跟 a heel and so "to follow". The sense "enough" is a separate development of the same word, heard in 足够 and 满足.