I think What3Words is in principle a nice idea, but it could have been implemented much better. I am thinking of the following:

- have a fixed pattern, e.g. adjective.adjective.noun.

- create groups of words and put them in hierarchies. E.g. noun->animal->predator

- cover the world with a one-dimensional Hilbert curve

- Increment the noun along the curve. When all nouns are exhausted, start with the first noun again and increment the adjective in the middle, a.s.o. (analog to how incrementing a number with several digits works).

With this approach, the location purple.flying.tiger would be next to purple.flying.lion.