An overflowing fullness; ample sufficiency; great plenty; profusion; copious supply; superfluity; wealth: -- strictly applicable to quantity only, but sometimes used of number.
- A great or plentiful amount.
- Fullness to overflowing: "My thoughts . . . are from the abundance of my heart” ( Thomas De Quincey).
- Affluence; wealth.
- Chemistry The amount of an isotope of an element that exists in nature, usually expressed as a percentage of the total amount of all isotopes of the element.