I think it's dependent on how much profit you're actually making. Revenue is irrelevant if you're in the red, as "start-ups" often are. That's what "growth oriented" means, imo. As companies mature certain other tasks are weighed more heavily, and in the grand scheme of things, if you're a mature company, growth isn't the number one priority. Rather maintaining your marketshare, and preventing other startups from taking your share of the pie takes up more resources than actual growth.

However I would never ever use "start-up" to describe myself, but rather only others.