Full Idea
On one possible description, an element is what is found last when bodies are taken apart, and what is found first when bodies are generated.
Gist of Idea
Elements are found last in dismantling bodies, and first in generating them
Source
Albert of Saxony (On 'Generation and Corruption' [1356], II.3), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 2.1
Book Reference
Pasnau,Robert: 'Metaphysical Themes 1274-1671' [OUP 2011], p.17