A fun phrase to say when somebody is eating something, the original usage of this word began as "nom nom nom" and was largely used online for lawlcats and the like. After the popularity of "dot com" in song and web, the dot com was added largely because it rhymed.
Chelsie : This apple is good...
Albert : om nom nom dot com :)=
A. A common phrase used by the heavy in Team Fortress 2. The line is usually executed upon eating a sandvich to boost his health.
B. The cutest and funniest girl on xbox live. She speaks her mind and can make any game fun to play. Known best for her adorable giggles and witty attitude.
A. Medic - "I NEED ASSISTANCE! I AM ON FIRE"
Heavy - "Baby man, Sandvich is MINE!" eats sammich, "om nom nom, om nom sandvich is DELICIOUS"
Medic dies.
B. Guy 1 - Dude I played with chick yesterday on L4D and she was possibly the funniest and most adorable person ever.
Guy 2 - That could have possibly been om nom sandvich, she's pretty epic.