Forefront means the leading position or the most important or noticeable place in something. When scientists are at the forefront of medical research, they're doing the newest, most advanced work that others will follow. When a student is at the forefront of her class, she's among the top performers.

Today it's used more broadly. A company might be at the forefront of electric car technology, meaning it's ahead of its competitors. A teacher might put literacy at the forefront of her classroom priorities, making it the central focus.

You'll often see forefront paired with “of”: at the forefront of innovation, in the forefront of people's minds. When something is in the forefront of your mind, you're thinking about it constantly. It's right up front where you can see it clearly, not buried in the back of your thoughts.