"smile on face". Because when instant messaging, most of the time you don't actually "laugh out loud" (lol), you just have a smile on your face.
lawllady121: should I wear socks?
forestcowsfall: you should always wear socks. they are great.
lawllady121L: sof
forestcowsfall: you should always wear socks. they are great.
lawllady121L: sof
by neucool December 25, 2007
by LegendChild27 August 26, 2021
by Gangsta69 May 7, 2005
by Ross020 September 21, 2011
n. Slap on Forehead. Usually said (on MSN or any form of instant messaging online) when the other person has said something extremely stupid or "uncool". The letter equivalent of the now common =.=". Sof is used for those who are deprived of newer versions of MSN which allows them to send and receive custom emoticons.
by eccentric.joker August 1, 2006