It used to be that Entrepreneur meant someone who started something, and Engineer meant someone with an engineering degree. If you were an early employee, you were certainly entrepreneurial, but not an entrepreneur; if you programmed but hadn't studied engineering, you were a programmer or a developer.
When I was working for UniTeller, a money transfer startup doing family remittances to Latin America, in 2004-2005, my boss called my El Ingeñiero Elpern (Engineer Elpern) , but this was a conscious effort by him to pump me up in the eyes of our latinoamericano partners, who have great respect for titles. We both knew the game we were playing and that we were being a little hand wavy with the word. I have a computer science degree but not an engineering degree, and frankly being called an engineer made me a little uncomfortable.
Over the past couple of years however I've noticed the usage of these words become much looser, particularly in the startup world: people without founder experience are calling themselves entrepreneurs, and people without a real engineering or computer science background calling themselves engineers. When it's just one person, you can say they're exaggerating. When it's a few, you can rant about people who don't know what the words mean, and hope it's just a fad. When it becomes the norm, you have to accept that language has changed and go with it.
This raises the question: if the entrepreneur title no longer requires starting something new, and the engineer title no longer requires the study of engineering, what do these words mean?  Is anyone with startup experience an entrepreneur, and anyone who can code an engineer? Or is there a particular bar for using these terms, like being a high-level employee at a startup or being particularly proficient at coding?
Oh, and I'm now an entrepreneur and an engineer, according to my Twitter and About.me profiles.
 A uniquely Latin American title that is analogous to the use of Dr. to mean someone who has an MD, but for an engineering degree.
 In the startup community we don't confer these titles with formal status, but they still manifest themselves in the headlines we write for ourselves, whether on About.me, LinkedIn, or a company site, to say nothing of the way these terms define our self-image.