“In the pocket”

“In the pocket” is a term often used to explain when a rapper or musicians writes or sings their lyrics in a way that makes the individual syllables land on a particular note or beat of a measure. This is what makes the lyrics sound like it goes with a beat. Almost as if the beat is carrying the words. It can be a synergistic feeling when accomplished. Therefore sometimes the term is used metaphorically to indicate someone is in the flow state. Or rather that things are falling in line perfectly.