Do we know who was the person who named black holes "black holes" and what lead him/her to call them this?
The physicist John Wheeler (1911-) is credited with the term "black hole" which he first used in 1967. Before him the idea existed of a star from which not even light could escape, but they were known as "dark stars" or sometimes "frozen stars". Wheeler is renowned for his ability to put complex ideas into simple and very descriptive terms. He is also credited with the word "spacetime". Why exactly he came up with the term "black hole" I'm not sure of, but you might be able to find out in his autobiography Geons, Black Holes, and Quantum Foam: A Life in Physics. Another book with a nice history of black hole science is Black Holes and Time Warps by Kip Thorne.
Karen was a graduate student at Cornell from 2000-2005. She went on to work as a researcher in galaxy redshift surveys at Harvard University, and is now on the Faculty at the University of Portsmouth back in her home country of the UK. Her research lately has focused on using the morphology of galaxies to give clues to their formation and evolution. She is the Project Scientist for the Galaxy Zoo project.