a euphemism for cocaine in the presence of non users. Derived from frequent sightings of people at 4 hour lunches at public restaurants, during which they consume nothing but lemon-water and cigarettes, followed by sporadic trips to the B-room and more lemon-water.
Chop the end off a lemon then insert Into the rectum with the chopped end facing out. Tighten and relax the nipper valve till the adequate amount of brown lemon water is added to your favourite soft drink.
'what did you put in my Fanta dude, it tasted tangy?'
'ohh that... I just added some brown lemon water, nothing to worry about'