What is Kum Lan?
1.
Original Meaning:
To suck on a penis.
But the term has been adapted by youngsters in Sing Ga Pore, they use it more freely, probably in any sentence.
"Go home leh, you go extra classes
kum lan ah?"
See
2.
not smart, act of stupidity
you very kum lan leh, so easy also dunno.
See