Language difficult to understand because of bad form

One word substitute is Jargon.

Rhetoric: the art of effective or persuasive speaking or writing, especially the exploitation of figures of speech and other compositional techniques.
Jargon: special words or expressions used by a profession or group that are difficult for others to understand.
Pedantic: excessively concerned with minor details or rules; overscrupulous.
Verbatim: in exactly the same words as were used originally.