Definitions

1. noun

A French surname.

“The famous mathematician Émile Borel was known for his work in measure theory.”

2. proper noun

A type of space in mathematics, specifically a topological space where every point is an open set.

“The Borel space is a generalization of the concept of a Borel set.”

3. adjective

Related to or denoting the Borel sets or the Borel hierarchy.

“In measure theory, a Borel set is a set that can be obtained from open sets through a countable number of set operations.”