Macro/enum prefixes are unclear, or conflict with each other

For example, what is FF_? Fake floor flags, or frame flags? Is SF_ for sound flags, skin flags, or the prefix for freemethod_t? Is RF_ for rendering flags, or the prefix for raiseflag_t? MD_ and MD2_ could be a bit more verbose. What does GTC_ mean? Do you know what LFTNS_ stands for? (It stands for Lua File Transfer Node Status.)