I've always thought it was interesting that in English there are lots of different words which mean the same thing but a different scale - like pebble / rock / boulder. It could easily just be little rock, rock, big rock. In a lot of cases the distinction does matter though, because what we can _do_ with a thing changes at different scales. We can throw a pebble without really hurting someone, a rock would be mean, and a boulder would mean you're a giant.