Scarcity
In economics, scarcity is defined as the condition of human wants and needs exceeding production possibilities. In other words, society does not have sufficient productive resources to fulfill those wants and needs.
Alternatively, scarcity implies that not all of society's goals can be fully attained at the same time, so that trade-offs are made of one good against others. In an influential 1932 essay, Lionel Robbins defined economics as "the science which studies human behaviour as a relationship between ends and scarce means which have alternative uses."
The word scarcity is used in an economic sense whenever the supply of resources is inadequate to satisfy human wants at a particular time.