A saying of Caribbean origin which quite literally translates as "the chaps over there" or "those fellows yonder". The saying has found it's way into British street use mainly due to the influence of gangs and/of rapists in urban areas. Nowadays it has evolved to a greeting or to refer to anyone else of similar mental capacity.
Gregory: "oh my daze man dem, has you bin heerin NDubz new record?"
Terrence: "i know it mandem they fo sho' wont think twice about ending manz life, y ou get me?"
Gregory: "we got no doe bro, lets pretend our position is enviable"
Terrence: "god, we is spaz'"