This is the 1187th most frequent Spanish word.
pies
"Feet" (plural of "foot").
The word "pies" (feet) is used as the subject of the sentence to refer to the physical parts of the body used for walking.
Los pies son fundamentales para caminar.
Feet are essential for walking.
Here, "pies" (feet) is used to denote the specific area of the body experiencing pain due to activity.
Me duele uno de mis pies después de correr.
One of my feet hurts after running.
In this sentence, "pies" (feet) is described as the part of the body that is safeguarded by shoes from external elements.