# Definition:Corollary

Jump to navigation
Jump to search

## Definition

A **corollary** is a proof which is a direct result, or a direct application, of another proof.

It can be considered as being a **proof for free** on the back of a proof which has been paid for with blood, sweat and tears.

## Linguistic Note

The word **corollary** is ultimately derived from the Latin **corolla**, meaning **small garland**, or the money paid for it.

Hence it also has the sense of **something extra**, **lagniappe**, **freebie**, a **cherry on the top**.

## Sources

- 1998: David Nelson:
*The Penguin Dictionary of Mathematics*(2nd ed.) ... (previous) ... (next): Entry:**corollary** - 2008: David Nelson:
*The Penguin Dictionary of Mathematics*(4th ed.) ... (previous) ... (next): Entry:**corollary** - 2014: Christopher Clapham and James Nicholson:
*The Concise Oxford Dictionary of Mathematics*(5th ed.) ... (previous) ... (next): Entry:**corollary**