It is a name used to refer to a stereotypical man, who is in love with his car and practices car tuning. Other characteritics would be wearing a mulet, watching football (and Pimp My Ride), drinking a lot of beer, calling his wife "mum", etc.
"Un mec qui pose à côté de sa voiture sur sa photo de profil, c'est clairement un jacky!"
"A guy posing next to his car on his profile pic is clearly a jacky!"
Submitted August 2020
Confirmed by 4 people