What is Siu?
1.
An acronym for "suck it up"
Person 1: Ow, I bumped into that wall.
Person 2: Man, SIU go
beast it
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2.
Acronym for Special Investigation Unit for law enforcement/prosecutors and insurance compaines
When that
boatload of coal claimed whiplash, they called SIU in to videotape them playing basketball
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3.
a unit of measurement equalling 5'0"
Slocum Hall's rotunda is about 3 sius tall.