What does it mean when a job is referred to as "c-level position"?

Given the job description, I’m guessing it is “cabinet- level” or something similar – this is a senior position (and they apparently had to raise the job description level so that it would be “c-level”). I’ve never heard a job referred to in this way before, and c-level in this case sounds like it’s very high up . Anyone else familiar with this term? Thanks.