What does "meridional" mean?

Meridional: Having a southern aspect; southern; southerly. Offices that require heat ... should be meridional. Sir H. Wotton. Meridional distance, the distance or departure from the meridian; the easting or westing. -- Meridional parts, parts of the meridian in Mercator's projection, corresponding to each minute of latitude from the equator up to 70 or 80 degrees; tabulated numbers representing these parts used in projecting charts, and in solving cases in Mercator's sailing.