[Firegarden]

Senior Engineer usually means someone with a number of years experience. An easy number is 10 however this isn't the only thing. Generally you have worked on enough coding projects that you are wise in how you put forward your effort. Also I would assume a SR Engineer has a good understanding of software design patterns. When I started out I thought that OO concepts were enough to master C# but everything changed once I started to grasp design patterns. I think SR generally means you have a certain amount of experience paired with a strong ability to code.

[k__]

I had the feeling it was mostly time based.

When I tell a recruiter I worked for 7 years as a dev, they often categorize me as a senior.