The combination of the words Shady and Canadian.

Shady- "illegitimate. underhanded. dishonorable. corrupt. sneaky." (www.urbandictionary.com/author.php?author=524)

Canadian can be the white person's alternitive to 'nigger'.

i.e. Shady ass Nigger.
Wow, that dude is such a shadian, never keeps it real.

or;

1: Who ya talkin' to?

2. Tramell
1: Ughh, nasty shadian.
by Spazmo017 December 31, 2010
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