In a drum fill could be as simple as one note, or as busy as a full bar of information. If I am playing a groove for four bars, or eight bars, or a certain section of a song, what you usually do it transition and connect phrases by a drum fill. Now, if I had to stick a definition on it, it would basically be a transition, and what I'm talking about is a transition between phrases. find this particular groove is in the top 100 classic sampled Hip Hop grooves.
Also, a crash cymbal typically follows a drum fill on the beat 1 of the following phrase.
