A workstation is were you do your work. In the tech world this is at your computer.
The term became poplar when more than a PC was required at work — particularly in the emerging 3D graphic design world that made Silicon Graphics and NeXT workstations in demand. For a very long time this meant that your workstation was a high-powered desktop computer.
These days your workstation is almost always your laptop possibly connected to additional screens and devices from your desk, or perhaps at a coffee shop. It is far more rare today to see developers using more than a single computer even if they change up the what its connected to depending on where they are.
Laptops like the Dell XPS sport the kind of power to handle everything except high-end gaming.
[What computer should I get?]