He's also the mathematician who worked on the Manhattan Project and was asked to confirm the calculations that setting off the first test blast would not create a fireball that would burn up all the oxygen on the planet!
I do not know the origin of the term "Manhattan distance". https://en.wikipedia.org/wiki/Taxicab_geometry says the concept comes from Minkowski in the 1800s, and a Google Scholar and Google ngram search suggest the term originates from around 1960, and the more common older term was "rectilinear distance".