sit next to Nellie
sit next to Nellie
old-fashioned To work alongside a person with a lot of experience so as to learn how best to do a job by watching them work. It used to be the case that new recruits would just sit next to "Nellie" when they joined the team; now, with how quickly technology is advancing, it's often the new recruits who have to explain how things work to the older members of staff.