a combination of the words: blah, argh, and ugh
can mean a variety of things including bored, dissatisfied, unhappy, angry...etc...
Internet Conversation:
Person 1: Hey, What's up?
Person 2: Nothing much... Todays a really really boring day!
Person 1: BLERGH
Person 2: Yup. I think that sums it it all up.
A word said when you dont know what to say, dont care of the topic, have no idea what theyre talking about, or when the convo has died and you don't feel like finding something interesting.