Czwórniak — A Polish mead, made using three units of water for each unit of honey. 3lb/gal
Trójniak — A Polish mead, made using two units of water for each unit of honey. 4lb/gal
Dwójniak — A Polish mead, made using equal amounts of water and honey. 6lb/gal
Półtorak — A Polish great mead, made using two units of honey for each unit of water. 8lb/gal
... how the... this doesn't seem physically possible. Poltorak would start around 1.264 gravity and end around 1.118 if it hit 20% ABV.