I've seen this distance measurement mode referred to as Manhattan distance (https://en.wiktionary.org/wiki/Manhattan_distance https://en.wiktionary.org/wiki/Man

I've seen this distance measurement mode referred to as Manhattan distance (https://en.wiktionary.org/wiki/Manhattan_distance https://en.wiktionary.org/wiki/Manhattan_distance), but it's interesting to see the full theory around it (and of course taxi-cab geometry is the more properly accepted name).