I believe that you mean abbreviations and acronyms such as F (female), M (male), BBW (big beautiful woman), Bi (bisexual), LDR (long distance relationship), etc. See the link below for a guide.
Androgynous
water sports
In personal ads it means "Friends with Privileges"
transsexual for male
NSW stands for N-new S-south W-wales
In the personal ads that I have seen, LOS means Lost or Stolen.
Androgynous
For sex :)
Long Term RelationshipLTR in personal ads means long term relationship.
OHAC mean in Relationship
friends with benefits.
Bareback, or no condom
water sports
In Search Of
professional
Pay to play
"short Message service" in other words text. It's not exclusive to personal ads.