M

M/F? - Male or Female?
M8 - Mate
MEGO - My Eyes Glaze Over
MHBFY - My Heart Bleeds For You
MHOTY - My Hat's Off To You
MM - Mama Mia!
MMD - Make My Day
MO - My Opinion
MorF - Male or Female
MOTAS - Member Of The Appropriate Sex
MOTD - Message Of The Day
MOTOS - Member Of The Opposite Sex
MOTSS - Member Of The Same Sex
M$ - A well-known software company
MSG - Message
MTBF - Mean Time Between Failures
MTF - More To Follow
MYOB - Mind Your Own Business
MYW - Makes You Wonder

N

N2M - Not too Much
NADT - Not A Darn Thing
NALAYL - Not As Long As You Live
NBIF - No Basis In Fact
NC - No Comment
ND - Nearly Done
NE - Any
NFW - No F'ing Way
NGAS - No one Gives A S***
NIAMY - Not In A Million Years
NIFOC - Nude In Front Of the Computer
NIICHI - Not If I Can Help It
NIMBY - Not In My Back Yard
NIYL - Not In Your Life
NM - Never Mind
NMH - Not Much Here
NMJC - Nothing Much, Just Chilling
NNTA - No Need To Answer
NOYB - None Of Your Business
NOYL - Not On Your Life
NP - No Problem
NRN - No Reply Necessary
NRN - Not Right Now
NRP - None Real-time Processor
NTOOT - Nine Times Out Of Ten
NTW - Not To Worry
NWIH - No Way In Hell

O

OAO - Over And Out
OBTW - Oh, By The Way
OEM - Original Equipment Manufacturer
OIAM - One In A Million
OIC - Oh, I see
OL - Old Lady
OM - Old Man
OMG - Oh My God
OOTB - Out Of The Box or Out Of The Blue
OOTC - Obligatory On Topic Comment
OPM - Other People's Money
OT - Off Topic
OTF - On The Floor
OTOH - On The Other Hand
OTP - On The Phone
OTT - Over The Top
OTT - Off The Topic
OTTH - On The Third Hand
OTTOMH - Off The Top Of My Head
OYA - On Your Ass