Frustrated response to something said. Passionate as well.
You know what?!!!! That ain't even right what you just said!
by GloJaz June 28, 2015
A song by T.I.

When someone recognizes, acknowledges and agrees with a statement somebody has made.
Guy 1: That was a sick touchdown.

Guy 2: You know what it is.
by BigThingsPopping August 24, 2008
The expression ‘you know what’ is when one may say to another to get their attention, in a conversation. One may say this expression several times throughout one conversation to ensure they still have the attention of those participating in the conversation.

‘you know what’ also is when your stating to someone about something there not aware of , or when someone constantly pays them out they use the expression.
Example
Your outfit looks like your going clubbing not to work!
‘you know what’ no one likes you!
by NATASHACAR January 13, 2011
Meaning : a person wants you to give them something that belongs to you. This is normally said by the person who is robbing victims.
by DoneDeal July 19, 2018
Prison slang meaning you shouldn't need any explanation about the results of what you did. Whatever you did or do, it's going to get you beat the fuck up.
You stole from everyone, you snitch to the cops. Punk bitch, you know what time it is.

If you ever cross me, you know what time it is.

If you disrespect my mom, you know what time it is.
If you don't pay your taxes, you know what time it is.
by Drpenispopper February 18, 2019
A phrase used to relate a certain situation to a "known saying", the saying is mentioned by unknown people referred to as "They".
You know what they say, Karma's a Bitch.
by Nadims January 7, 2017