a radioactive transuranic element
an abstract part of something
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
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
the most favorable environment for a plant or animal
the situation in which you are happiest and most effective
a straight line that generates a cylinder or cone
one of four substances thought in ancient and medieval cosmology to constitute the physical universe
