The Rice University Neologisms Database

something that is fantastic or the best. "Da Bomb" is word used in the nineties by surders, skaters, rappers, etc. "Da" often replaces "the" signifying slang or causual use. “Da” is generally only used in casual conversation. If someone states that something is “da bomb” it is like saying it is fantastic. Perhaps people related a bomb to being explosive or really cool like an actual bomb. On the other hand, it may be used because it creates a feeling of awe, maybe like an explosion of a bomb.