euclid
/ˈjuːklɪd/Definitions
1. proper noun
A Greek mathematician, considered the father of geometry, who lived in the 3rd century BC and is famous for his work in ‘Elements’.
“The Greek mathematician Euclid is known for his famous work ‘Elements’, which is one of the most influential books in the history of mathematics.”
2. noun
A geometric theorem or problem, especially one that is difficult to solve.
“The math class discussed Euclid’s famous theorem about the sum of angles in a triangle.”