A few months ago, Inc. magazine taught me that the classic definition of an entrepreneur was coined 37 years ago, by Harvard Business School professor Howard Stevenson. An entrepreneur, he said, is someone who pursues opportunities without regard of the resources currently under control. I repeated that definition to someone else. “In other words, a fantasist,” he said. But the two things aren’t synonymous. A fantasist is someone who says, “If I win the Lotto, I’m going to buy a Ferrari.” An entrepreneur is someone who says, “I want to start a company, but I have no money and no staff. Given that, what are the steps I need to take to get there?” That definition makes a lot of sense. But I have another definition for entrepreneur, one that is more focused on leadership. Here it is: The entrepreneur is the one without whom the endeavor would not happen. This is not to suggest entrepreneurs are lone cowboys -- far from it. Any entrepreneur who doesn’t build a team and trust it to perform is fighting an uphill battle. It’s also not to suggest that the team isn’t important. If the entrepreneur fails at the team-building process, failure is virtually certain. The team is essential. But I’m talking about the driving force, the person who has put her heart and soul and reputation on the line to turn a dream into reality. This is the distinction: If you don’t want to work for the entrepreneur, the entrepreneur will find someone else to fill your role. If the entrepreneur doesn’t do what entrepreneurs do, the project wouldn’t go ahead at all. An entrepreneur might hire a developer. The developer might be the best developer in the world. This developer is directly responsible for creating an amazing product that people love to use. Some people say that, without this developer, the product wouldn’t exist. And in one sense, they’re right: the developer is the person who did the work. But in another sense, they’re wrong. If that developer didn’t want the job, the entrepreneur would hire another developer. Maybe it would only be the second-best developer in the world. But the project would continue. It’s not just about developers, obviously; the same holds true for marketers, salespeople, admin staff -- anyone who contributes to the operation of a start-up. Of course, the entrepreneur might not be very good at this; he might pull together a bad team that isn’t capable of delivering on the vision, or she might not be persuasive enough to pull together a team at all. But this is the entrepreneur’s job: to get the right people to believe in the shared vision and contribute to making it a reality. And let’s face it: there are often moments in start-up life when it’s tempting to quit. The deal falls through at the last minute. That key developer -- the best one in the world -- gets a job at Facebook. The rest of the team starts to wonder whether this whole thing is really just a crazy dream, after all. The entrepreneur is the person at the center of the chaos, the person who keeps it all together when the money doesn’t show up or the media hate the product. And, in those moments when things are falling apart, there’s rarely a right answer. Persist and succeed, you’re a visionary. Persist and fail, you’re an idiot who should have given up long ago. Pivot and succeed, you’re a market-driven, egoless leader who can adapt to dynamic realities. Pivot and fail, you’re a spineless follower with no vision of your own. The entrepreneur is the one who decides whether we’re investing in one more iteration or whether it’s time to call it a day. Because when the entrepreneur calls it a day, everyone goes home. That’s the definition of an entrepreneur. Thoughts?