Means funnier that lol, used in really funny positions when lol or rofl just won't do.
Kik has many "spin off" words. Those words include:
kikass - Funny and Awesome
kiken - Super Sweet
karatekik - making fun of people in the most funny way
kiked - Made someone laugh really hard
Person One - "Did you watch this movie?"
Person Two - "Kik! it was so funny!!!"