Are コミュ症 and コミュニケーション障害 informal/slang words in Japanese?

Question

I would like to know the usage of these words. In English it seems to me that communication disorder is a more technical, clinical term.

But if I try to find the definition of コミュ症, such as on Wiktionary or other places, the definition is very informal:

(informal) having despairingly poor ability to converse with people due to social anxiety.

And at japandict.com

being bad at communication, being unsociable

I've seen this term translated at communication disorder in at least one manga (Komi Can't Communicate) and probably in another (Watamote), but to me it does not seem equivalent to the English word. Communication disorder applies to a broad range of disorders far beyond just social anxiety disorder, and it isn't used so informally as to just mean "bad at communicating".

Thus, I would like to know more about the definition of this word and how it is used in different situations, and whether there are circumstances it would be equivalent to the English "communication disorder".

Answer 1

It's safe to say コミュ障 (or コミュ症) is 100% slang. As far as I remember, it has always been used in this short form since it began to be used a few decades ago. It's never used in serious medical contexts.

The term コミュニケーション障害 exists as pure medical jargon, and it refers to the same thing as explained in this English Wikipedia article. There is an academic society for this "disorder". Many Japanese articles on this subject explicitly state that it's very different from the slang term コミュ障. However, コミュニケーション障害 is not widely known even among professional health care providers, presumably because it's nothing more than a hodgepodge of disease entities that are unrelated to each other.

Therefore, it sounds very wrong to me to "expand" コミュ障 to コミュニケーション障害. But since ordinary English readers would not understand "komyusho", I think the translators could think of no choice but to use "communication disorder".