1. To live or work in very close proximity to one, such that one has a great impact or influence. I adored my older brother growing up, and I pretty much lived in his pocket until he left for college. We've been sharing an office for about two years, but we're starting to get tired of living in each other's pockets.

2. To live under one's direct control or influence, especially in a financial capacity. It's pretty obvious that our national legislators are all living in the pockets of major corporations. You'll never get justice for the crime—half the police force is living in the mafia's pocket.