agile is made up of ag- meaning "to do" and the Latin suffix -ile which means "pertaining to; like; having the character or quality of." Thus, agile means "having the quality of doing or acting" or "able to do or move quickly and easily; nimble."
Peter is agile and athletic.
A word based on agile is agility, meaning "the ability to move quickly and easily."
The quarterback had remarkable agility.
