I did some searching, and didn't really find definitions around usage.
Looking at his stats, he's very comparable to Aaron Jordan. Good defensive rebounder, low turnover rate, high offensive rating, and shoots often and well from three, usually assisted. Most notably, they both play a lot of minutes but have the lowest usage of all starters. Aaron Jordan has been described as a role-player, so I don't think it's unreasonable to describe Smith as the same.