The dictionary defines it as "the action or process of setting something in motion."
Warby Parker co-CEO Neil Blumenthal has another definition: "A startup is a company working to solve a problem where the solution is not obvious and success is not guaranteed," he told Forbes' Natalie Robehmed.
Perhaps the most precise definition of a startup is that there isn't one. Being a startup, a lot of founders believe, is a state of mind. It's not a word that's restricted by the number of years a company has been in business, or the amount of revenue a business pulls in.
Jan Koum the co-founder of $19 billion WhatsApp, says a startup is a feeling.
"I think [a startup is] not connected not with time," he told journalist Nastya Chernikova (Google translated from Russian). "They say that age - it's not the number, but how it feels. For example, I do not feel like I'm 38. [Our] company is five years old but we are moving quickly and make decisions quickly, we build products, so we are still a startup. We do not have meetings, conferences etc."
Another entrepreneur stated it more bluntly. Homejoy CEO Adora Cheung tells Forbes, "[A] startup is a state of mind. It's when people join your company and are still making the explicit decision to forgo stability in exchange for the promise of tremendous growth and the excitement of making immediate impact."