The meaning of the word entrepreneur has evolved. How entrepreneurship is defined now is drastically different to how it was 5+ years ago. The wikipedia definition even lends a notion to it's definition being outdated:
Entrepreneurship has traditionally been defined as the process of designing, launching and running a new business, which typically begins as a small business, such as a startup company, offering a product, process or service for sale or hire.
How our careers evolve has changed. We have become our own entities. Our own personal brands. This is true if you are the freelancer or employee number 140 at Dropbox. You are no longer hidden under the umbrella of a company. You need to step out into the light to be noticed. You need discover, build and promote your brand.
Along side our brand, we are running our own personal business. Through designers posting their latest creations to Dribbble and developers writing masterpieces on GitHub, we are constantly promoting our own personal company. We are showcasing our portfolios.
We have become completely decentralized from the company we work for and seen more as individual islands. This has a huge advantage as we can navigate across organizations with ease, solving challenges as we transverse. Progressing our personal business step by step. The flip side to these benefits is each person must now posses the skills to showcase their work in the right environments. Winning contracts and business opportunities. You must now, more than ever, be able to sell yourself.
You're already running a business. It's yourself. How you build, promote and execute on that business is what differs you. What makes you stand out from the crowd and progresses you forward.