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1.
Something someone would say if he has experience of any sort, particularly a soldier's battlefield experience.

All in all, this phrase is self-explanetory to whatever meaning you desire.
"Screaming, killing, explosions.....I've seen it all."
-a soldier

"Murder, punks, drugees..... man I've seen it all."
-a thug

"When she removed her thong man......I'VE SEEN IT ALL!!! ^.^ ^.^ ^.^ "
-a perv
by Dave May 04, 2004