ETYM Latin paucitas, from paucus few, little: cf. French paucité See Few.
1. Fewness; smallness of number; scarcity.
2. Smallnes of quantity; exiguity; insufficiency.
3. State of being few or small; scarcity; lack.

ETYM Latin raritas: cf. French rareté. Related to Rare.
1. A rarified quality; SYN. tenuity, low density.
2. Noteworthy scarcity; SYN. rareness, infrequency.

Quality condition of being scanty.

A small and inadequate amount; SYN. scarceness.
In economics, insufficient availability of resources to satisfy wants. The use of scarce resources has an opportunity cost.