The popular term"Fo shizzle my nizzle" is quite oftenly thought of as meaning "for sure my nigga". However, the true definition is, simply, "rub my dick".
(.)(.)
David said to Mandy"Fo shizzle my nizzle",which got him kicked in the Nizzle(if you know what i mean).
Sally said to Bob"Shall I Fo Shizzle My Nizzle?",Which scared Bob quite a lot.
This is not a word, period. It is some sillybullshit perpetuated my Snoop Dogg or P. Poodle or whatever he is calling himself this week. However, if you really want to judge it to the same standards as real words, it loosely means "Okay".