element

noun

1. an abstract part of something"jealousy was a component of his character"
2. an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system"spare components for cars"
3. any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
4. the most favorable environment for a plant or animal"water is the element of fishes"
5. one of four substances thought in ancient and medieval cosmology to constitute the physical universe"the alchemists believed that there were four elements"
6. the situation in which you are happiest and most effective"in your element"
7. a straight line that generates a cylinder or cone