exclammation;exhaltation; wonderment; a sure fire way to start off any sentence...
**sound out each letter ... O-M-G
1. O.M.G! I am not bossy!
2. O.M.G! I'm getting married!!
3. O.M.G, is she really going out with him?
4. O.M.G. This has got to be the most intellectual conversation I have ever had ....