This expression is supposed to imply a juxtaposition of a crass or offensive action against something that is held as sacrosanct by someone else.
Coined by Ben "Yahtzee" Croshaw
Coined by Ben "Yahtzee" Croshaw
"For four, what the fuck happened to Clive Winston, you pricks?! In his place we've got some multicoloured, giggly J-pop creature, and you can't play classic rock with that...thing. It's like cock-slapping the Mona Lisa."
-Ben "Yahtzee" Croshaw in his Guitar Hero III review
-Ben "Yahtzee" Croshaw in his Guitar Hero III review
by Platitude May 27, 2015
Get the Cock-Slapping the Mona Lisamug. A sex act when a young "artist" tricks an old dirty art teacher into holding up a empty picture frame. He then shoots "patronage" (i.e. semen) all over her face through the frame, and earns his A.
by SukyPirate November 16, 2009
Get the The ol' Mona Lisa Twistmug. 
Somebody who is popular with un-popular friends, somebody who everyone pays attention too but not their friends or the people their around, they get ignored while Mona Lisa is the center of attention.
Sarah is a Mona Lisa, I’m her best friend and I’m always around her but she’s the most popular person in school, so I get ignored and cast away when she’s talking to other people, it’s like I don’t even exist to them.
by Swallowcatz August 7, 2025
Get the Mona Lisamug. 
When a cleavage looks kind of perky and happy but also a little on the sad any unperky side at the same time.
"Have you seen Emily's breasts? Her tits are like "Wow!" but also kind of "Meh." at the same time... I feel like her cleavage is somehow smiling at me--but also frowning at me! It's like she's got that whole Mona Lisa Cleavage thing going on. You know, like auntie Sara."
by Turtleboy3000 September 19, 2016
Get the Mona Lisa cleavagemug. me complaining to my mum
teenager : 'mum I feel ill - don't think I can go to school today, mum my hair looks bad, mum why do I look like chicken little'
mum: 'pumpkin pie stop being a mona lisa'
mum: 'pumpkin pie stop being a mona lisa'
by Custard&mayo February 28, 2019
Get the mona lisamug.