A pretend language comprised of poorly pronounced or spelt German by a native English speaker. The word can be either thought of as partly german (hense the -ish) or a mixture between German and English (German-English with "engl" removed). Common attempted german words include sehr, grob (instead of groÃ) and anything you might expect to have learnt in a year at school.
Person1: Ish bin sehr grob. Mein kat izt grob. Ich kan nisht spreken doitsh...
Person2: That's not german, thats germanish.