WoW:API FontString SetFont

FontString:SetFont("font",size[,"flags"]) - Sets the font to use for display in the fontstring.

"font" is the name of a font size is the size of the font "flags" are any of OUTLINE, THICKOUTLINE and/or MONOCHROME

Usage

FontString:SetFont("FRIZQT__.TTF",11,"OUTLINE, MONOCHROME")