N-UNCOUNT 行話;行業術語;黑話 You use jargon to refer to words and expressions that are used in special or technical ways by particular groups of people, often making the language difficult to understand. 行話;行業術語;黑話
The manual is full of the jargon and slang of self-improvement courses.
手冊裏滿是有關自修課程的行話術語。
...the reading habits of 600,000 C2 males (marketing jargon for skilled manual workers).