This is the 14761st most frequent German word.
ostdeutsche
"East German" (referring to something or someone from Eastern Germany).
Here, 'ostdeutschen' is used as an adjective describing 'Landschaften', indicating that the landscapes are located in East Germany.
Die ostdeutschen Landschaften sind für ihre Schönheit bekannt.
The East German landscapes are known for their beauty.
In this case, 'ostdeutscher' is an adjective modifying 'Akzent', specifying that the accent originates from East Germany.
Ein ostdeutscher Akzent kann manchmal schwer zu verstehen sein.
An East German accent can sometimes be hard to understand.
Here, 'Ostdeutsche' is used as a noun referring to people from East Germany.