The answer to each clue below is a kind of "parlance" or conversation. For example, a home remodeler's parlance could be PANEL DISCUSSION.

1. Musician's parlance?
2. Chiropractor's parlance?
3. Billiard player's parlance?
4. Auto mechanic's parlance?

Answers:

1. Key words
2. Back talk
3. English language
4. Idle chatter

Credit:
Mark Bickham