look up any word, like the eiffel tower:
 
1.
A message sent on an IM client while the other person is offline.
I sent my boss an offliner, I hope he gets it on time.
by Vicrum December 19, 2007
 
2.
One who has yet to embrace the use of IM, microblogging, commenting, etc. as a means of communications and "social" relationship building.
My friend isn't on Twitter yet. Total offliner...
by juicecowboy August 19, 2009
 
3.
One who leaves during chat on IM, such as MSN, AIM, Yahoo, etc.
Franco says:
so yeah, lol that IS funny!
Your receiver is not online, so your message was not sent.

Franco: OMFG what an offliner!!!!
by ripples6542 January 19, 2008