A baby jumper shot in basketball is a term used to refer to a small jump shot, that is attempted very close to the basket. A baby jumper is done when a player finds themselves at a distance not quite close enough to make a layup, however not far enough that is considered a mid-range jumper. The baby jumper is not very used in modern basketball. Players will not often find themselves trying to score in a distance that requires a baby jumper.
Also, with the increased use of analytics in basketball, players look to either take high conversion shots like layups, or 3-point shots. Baby jumpers do not fit any of those categories, so teams try to avoid it. However, complete players must develop a consistent baby jumper, especially post players like centers and power forwards who are specialists in scoring in the paint and close to the basket.