Similar to OMG (Oh my god!), but ending with a fashionable "osh" to imply "Oh my gosh!", which isn't "Oh my god!", which is important, if importance was the issue. Which it's not.

It's just short for "Oh my gosh!".
Omgosh that beast is hawt.
by Serra September 18, 2004
Less offensive than "Oh my God" It became a combination of "Omg" and "gosh." Used as a expression of surprise, shock, or even joy
"Hey did you hear school's canceled today?"
-Omgosh, awesome!
Or

"Omgosh, did you hear what happened to her???"
by Tasha H (O yea!) May 16, 2005
Spin-off of OMG or OMGosh. Adds a bit of flair and emphasis for fun.
Omgoshness, Becky. Look at her butt!
by Darneezy May 25, 2016
For anyone that decides omg is overrated, and feels the need to be different. Also has a cutesy feel to it.
by SHES.ON.HER.BLOB June 18, 2010
means oh my gosh. used by bible bashers who dont want to use gods name in vein.
omgosh look at that!
by chav hunter0 August 8, 2006