A declaration of deep male rage, usually said out loud in a whispered scream; emphasis and lengthening on "Sac". "Sac" in "Oh My Sac" refers to the scrotum, however, females may exclaim "Oh My Sac" with the understanding that their scrotum is proverbial, and lasts merely for the duration of the phrase.
The car in front of me hesitated too long and the traffic light turned back to red. "Oh My Sac!"
by Deanius August 19, 2008