Simply "asshole" spelled backwards. It's meant to be funny cause it sounds spanish but anyone who speaks spanish will have no idea what your talking about.
It's 'oh, shit!' fast, and cut off into 'oh, sh--!' or a way to sarcastically make a comment to/about someone trying to be intimidating. (: people say it without even knowing so it might as well be a word!
kid: "back up!"
person (talking to friend): "OHSH! i'm SOOO scared" (sarcasm)
OpsSec, OPSSEC, or Opssec. Is AOL Operations Security Team. They take care of SecurID and password issues for employees. While also maintaing account security of elite and privileged accounts.