Technical language from the workplace or specialized fields of knowledge is called

A) idiom

B) slang

C) dialect

D) jargon

Technical language from the workplace or specialized fields of knowledge is called D. jargon.

Idioms aren't usually technical - those are phrases such as pull one's leg, raining cats and dogs, etc.

Slang is language used by a certain population, for example, young people's slang.

Dialect is just a type of a language spoken in another country, for example, American, Australian, and New Zealand English are dialects of the English language.