A disciple is literally a follower, a pupil, a learner, an apprentice. He is one who has dedicated not only to follow his master but also to become like Him.
Reference: Growing a Healthy Church, Moody, 1991, p. 18. Get this book!
A true discipling ministry will include every aspect of winning people to the Savior, building them up in their faith, and equipping them to win and build others.