A cooler way of asking a person if they know what you mean/understand what you are saying to them. Usually attached to the end of sentences for added effect.
When said normally in a sentence "gnomesand" sounds like "know what I'm saying," phonetically. If the word is said fast enough, the listener won't be able to tell the difference.
This makes for an awesome addition to one's everyday hip vocabulary without all the ghettoness of true Ebonics.
Hey Kyle did you catch that new Terminator movie? I thought it was pretty good, but it doesn't even equal the caliber of the first two movies, gnomesand?