A very long time ago I read a math book that was not so much about proving anything or actually about learning math, but it was about the history of math and influential historical people and also about math concepts. It was written in the dictionary format and it was for adults – I mean, it's not an "abc" children's math book like the ones I see when I try to search for this book.
I think the math book is quite known or at least not some obscure one. Anyone has any idea of the book I am talking about?
by fg_hj