What are some examples of advanced level vocabulary, in your profession, that an average person wouldn't know of?

It’s not really advanced level. It’s just industry jargon. Every industry, including religion, has its own specialized vocabulary. For the most part, people outside that category don’t know and use their special terms. It’s not that they’re secret, just that outsiders don’t have much need or opportunity to use them. A big part of orientation to a business or organization is learning their special words.

The same goes for the introductory level in a field of study: you have to learn the words peculiar to that subject matter.

One reason the number of words in a comprehensive English dictionary is so large compared with a well-read person’s ample vocabulary is that the dictionary has so many of those specialized words in it.

So, do you just want to know some jargon from various industries and professions?

@Jeruba Sure.

NAVY-
Head – toilet, both the instrument, and the chamber where it’s found.

Bulkhead – wall

We do Proto-Flight testing, which is almost as severe as prototype testing but not so severe that we can’t use that (expensive) item for Flight. Subsequent items get Flight tested, which is the standard level of severity to ensure it will work during Flight.

Music has its own set of specialized terms. Examples: solfège, interval, clef, key{, etc.