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2.
A person who is so ignorant or stupid that he/she is clearly "Operating On Brain Stem Only" --OOBSO-- with no higher brain activity.
1. The clerk in any American store who does everything by rote and, if asked a question even slightly out of the expected, is totally unable to respond.
Clearly an OOBSO.

2. George W. Bush, OOBSO extraordinaire.

3. Loud mouth fools on talk radio, OOBSO paradise.

4. Sarah Palin, Brain Baked Alaskan OOBSO.
by Diogenesparis April 14, 2009
 
1.
A typical no-clue idiot that you find everywhere you go.

Stands for "Operating On Brain Stem Only".
Clerks at fast food places who memorize their lines and who, if you ask anything out of the expected questions, are totally bewildered. What an OOBSO!
by Atticus Madison August 27, 2005