Common words:
* pedal
* pedestrian
* pedestal
* peddler
* pedantic
* pedagogy
Less common words:
* pedometer
* peduncle
* pediment
* peddler's
* pedology
* pedophilia
* pedologist
Words related to feet:
* pedal
* pedestrian
* pedometer
* peduncle (footstalk of a flower)
* podalic (related to the foot)
Other words:
* pedantic (overly concerned with minor details or rules)
* pedagogy (the theory and practice of education)
* peddler (a person who travels around selling goods)
* pedestal (a base on which something stands)
Let me know if you need more specific types of words, such as words related to a particular field or theme!