A phrase used for humorous effect in the middle of an online post to suggest that one is checking one's notes or research before completing the statement. It is often used to convey sarcasm or disingenuousness by suggesting that one has to verify what they are about to say because they can hardly believe it because it is so ridiculous. In social media posts, the term often appears inside asterisks (*checks notes*), which are commonly used in online communication to denote an action (which is usually stated in the third person present tense). Apparently the fight started due to a heated discussion over the highly controversial topic of *checks notes* cake. Congratulations for not having a meltdown on Twitter for *checks notes* 3.5 minutes.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.