By my understanding, a data scientist specifically concerns themselves with analysing large datasets. There's a big overlap with various other fields.
In astronomy, for instance, we're collecting so much data that it's difficult to analyse it all. It starts to pile up. And there's such a huge amount that some people (myself included) have spent years analysing data that others have acquired. Discoveries are still being made this way with second hand data.
Data science (including disciplines like data mining and deep learning) works to use this vast amount of data as best they can. It feeds synergistically back into the disciplines the data came from.
Though I'm not a data scientist, and I'd be interested to hear other takes on this.