Germglish is what native speakers of English (e.g. an expat) who spend too much time in a German-speaking country without looking after their English end up speaking and writing. They start speaking and writing in a way that's strongly influenced by German.
Alternatively, this can also be used to describe how some learners of English who are native in German
sound when they speak or write in English.
For example, they might use
words that sound like a German word in the
wrong context (so they might say they have the "actual" version of
something rather than the "current" version, because the German word for current, "aktuell", sounds like actual).
They also use more Germanic syntax and
grammar, with
funny hyphenation, comma usage, and weird plurals. See below:
"Germglish is an affliction that starts slowly. Unusual word selection is usually the first symptom. Uncomfortable syntax, might be seen next. German-oriented language is also already fundamental within the framework of this illness, as are those additional
words. By this stage, the hyphenation-problem is usually getting much more serious. These people may still have very-useful informations to share, but by this stage it is hard to follow the thread already, because their mother language word order is so destroyed by German-oriented-
grammar by now."
"I have no idea what that means. It's total Germglish."
"That woman might be American on
paper, but she spent most of her life in
Germany. She opens her mouth and it's just pure Germglish."
"I really need to visit
home more often - I just seem to be writing Germglish lately."