Literally: Go do a ass

Va' means "you go" and comes from the Italian word "Andare" which means "to go"

Fa' means "you do" comes from the Italian word "Fare" which means "to do, or to make"

un, is the indefinite article "a" in masculine form.

culo, means behind, or can be slang for bottom, or "ass"
by Rick Smith March 26, 2005
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