[Ger-Poland-Volhynia] What does "Rum" or "Rumunki" mean?

[Krampetz at aol.com]

While examining the detailed map of Lipno and area, at mapywig.org,  I  find
many village names preceded with "Rum" or "Rumunki".   
Google translates Rumunki as "Romanians".    
I did find that this question was asked on this list in 2005 and 'guessed'  
at,  
but no definitive answer.
 
Bob Krampetz
    Researching Krampic & Krampitz surnams (mainly  around Lipno).