> In _The Jazz Theory Book_, Mark Levine defines playing in the pocket simply as grooving, where the rhythm section is locked in and working as a unit. > in t

> In _The Jazz Theory Book_, Mark Levine defines playing in the pocket simply as grooving, where the rhythm section is locked in and working as a unit. > in the pocket - When the music is rhythmically in a groove. > groove - The “lock” between members of a rhythm section playing well together.