means kill yourself but if you wanna be an annoying little fuck and come up with an excuse to say it to someone, you could tell them it means "keep yourself safe"
1: lol kys
2: bro why would you tell someone suicidal to kill themselves
1: nah i meant keep yourself safe ahahahahha lol xdxdxdxd hHAHAHHAHAHhahhahahah im so funny
2: kill yourself
2: bro why would you tell someone suicidal to kill themselves
1: nah i meant keep yourself safe ahahahahha lol xdxdxdxd hHAHAHHAHAHhahhahahah im so funny
2: kill yourself
by Zewen E January 24, 2022
Get the kysmug. Ky is a good friend but will have no problem betraying you if he feels like he should. Ky is also a very funny person who makes people laugh all the time although ky is annoying most of the time!
you're so ky
by Johnnytest68 January 24, 2021
Get the kymug. It means “Kill Your Self”
by ABadB!tchFYM August 27, 2020
Get the KYSmug. by Jimmy Nick-Nathan January 10, 2021
Get the Ab Kyedmug. 
by Microwaves7143 August 20, 2021
Get the kysmug. kys is a term that five-year-olds or pissed off teenagers trying to be better than whoever they are arguing with online use to tell the opposite side to end thier life. The K stands for Kill, the Y stands for your, and the S stands for self. Many people who can't think of a way to have a comeback will act as if they think kys stands for Keep Yourself Safe, even though they very clearly know it truly is someone wishing suicide upon them.
1"kys kid, you're bad"
2"bro my team literally won what do you mean im bad"
1"kys kys kys kys kys kys kys bad bad bad bad bad skill issue skill issue kys kys"
or
1"kys kid, you're bad"
2"ok, i'll keep myself safe :D"
1"stop acting like a toddeler"
2"oh yeah? well you should kys"
2"bro my team literally won what do you mean im bad"
1"kys kys kys kys kys kys kys bad bad bad bad bad skill issue skill issue kys kys"
or
1"kys kid, you're bad"
2"ok, i'll keep myself safe :D"
1"stop acting like a toddeler"
2"oh yeah? well you should kys"
by H2o Eater June 27, 2023
Get the kysmug.