look up any word, like cleveland steamer:
 
1.
CSO
Community Service Officer.
University Employees that provide Escorts and Campus Security. They are often underpaid, overworked and stalked by their clientel.
Can I request an escort from a CSO.
A really cute CSO walked me home last night.
by suptrupe November 22, 2005
 
2.
CSO
Catholic schoolgirl Outfit
Hope she wears her CSO to the party; that baby rocks!
by SamBeeGees November 09, 2009
 
3.
CSO
Combined Sewage Event: typically used by public works departments to describe the unintended discharge of large quantities of raw sewage into lakes and oceans. CSO can also be effectively applied to the uncontrollable discharge of large quantities of excrement by an individual.
Where is Bob? He's been gone for over an hour.
He's in the bathroom having a CSO.
by THX1137 July 13, 2010
 
4.
Crakaz shot on sight

policy in many hoodz includin mine REXDALE
CSOS compton, detroit, east la lota stuff
by Desi_Doubkle December 07, 2007
 
5.
CSO
Completely Sold Out
USUALLY in regards to tickets to a concert of event
I hate it when tickets are CSO early
by MannyFresh September 05, 2005