Often used affectionately or as a casual greeting, but can be more derogatory especially in conjunction with strong language like fucking.
Why's Sam not here?
Because he's a chief.
That man is a fucking chief.
Person 2 - "He's being a chief because he pulled his god damn quad again, this is the 20th fucking time! Did you notice that mitch was chiefing as well for his torn labia?"
Person 1 - "No, but I do now... those fucking chiefs"
The most important promotion in an enlistedman's career, the title carries with it significant responsibilities, not limited to training and mentoring junior commissioned officers (15 or so years younger than themselves) and playing father figure to a bunch of juvenile imbeciles the Navy has the audacity to call sailors.
Chiefs are well respected by senior officers, feared by junior enlisted men and are treated like a general pain in the ass by far too many junior officers. Identified by their khaki uniforms, they maintain a separate mess that even a Captain can't enter without permission and cannot be demoted short of a conviction at Court Martial.
"You've been in 9 months, and know shit. Say that after you've put in 15 years."