I've been visiting the forum for 2 months now and I'm still confused by all the abbreviations.  Can someone explain to me what the following abbreviations mean?

MM - 女生的统称

ZT - 猪头，老公的昵称

LD - 1.long distance，2.领导（老公or老婆的昵称）3.应该还有其它意思，偶想不起来了

Thanks!