Looking at 足, now we can be pretty sure that it is related to foot, as its bottom part 止 hints. What does its upper part - 口 mean here?
To understand it fully, we need to check its Oracle Script - , with the help of Oracle Script of 疋 - . Even Oracle Script of 正 - can help as well.
Compring Oracle Script of 疋 - to that of 足 - , we can see that 足 is drawing of a ankle plus foot. For 止 is no longer used to mean foot, 足 is then used in place of 止. So 足 now means foot.
Comparing Oracle Script of 正 - with that of 足 - , they were so similar that some Chinese linguist argue that 足 and 正 used to be same character. For 正 has had its 口 part be simplified to a dash, 足 thus keeps 口 to differentiate it from 正.
There is more to get from drawing of 足. You might be surprised to know that 足 also has the meaning of enough. How can a foot be related to enough? Comparing Oracle Script of 足 - to that of 止 - again. We can see that 足 contains the meaning of walking towards a target place as 正 as well! Since 正 is to mean "marching to enemy place", 足 is then used to mean "marching back to hometown". A triumphant return means "the army has captured / plundered enough benefits", that is why 足 was also extended to mean enough. Make sense now?
Evolution history of a Chinese character can always be great help for our better understanding of it, as shown below. (Iamge take from www.vividict.com):
|Learn one Chinese Character a day - 足|
Now we have finished our learning of 足, it is time to enjoy a Chinese calligraphy to end our lesson today.