Basically, a long way of saying that something is true. Especially funny if you can get an adult, especially a teacher to say it because it makes them sound like they're trying to be hip. Can also be used in question form (e.g. 2)
Example 1
Person 1) I've finished everything.
Person 2) Really?
Person 1) Straight up no word of a lie
Example 2
Person 1) I've finished everything.
Person 2) Straight up no word of a lie?
Person 1) Hell yeah!
The No-No word is just not any word, it is the real world equivalent of "He who shall not be named" from HP, you can say it if you have a N-Word pass. I have one so, the No-No word means "Nigger or Nigga"
Yo dude, whats the craziest thing PewDiePie has ever said/done?
remember when he said The No-No Word on stream while he was playing PUBG oh yeahhh
A more appropriate way to use the n word if you’re not at least 1/8 black. It is also less offensive too. For those who don’t have access to the n word pass either.
My friend said the n word from a song, so I started saying “no no word” because my friend was black and I was white.