not

1. (litotes) Used to indicate the opposite or near opposite, often in a form of understatement.Examples: "That day was not the best day of my life. (meaning the day was bad or awful)"; "It was not my favorite movie of all time. (meaning the speaker dislikes or strongly dislikes the movie)"; "In the not too distant future my view on the matter might be not a million miles away from yours."not-comparable

2. (ironic, informal, originally African-American Vernacular) Used before a non-finite clause (especially a gerund-participial clause) or less commonly a determiner phrase to ironically convey some attitude (e.g. surprise, incredulity, amusement, embarrassment) towards something.Examples: "Not me writing example sentences again."; "Not me crying by the end of that!! You are a brilliant, beautiful human who deserves no less than the world. Thank you for taking the time to watch unicorn store. It’s a film that means so much to me."; "[Keke] Palmer tells Hoda Kotb and Jenna Bush Hager to “mind y'all's business” when they ask about her relationship with [Darius] Jackson. ¶ “Not y’all trying to get into it! They trying it on the Today show,” Palmer joked when the subject was first brought up on Today With Hoda & Jenna."informalironicnot-comparable