Hoskins, 25 joined the Championship side (who won promotion last season) from Bristol Rovers in May 2011 and has netted just once in nine outings this season; that came at Cardiff City in a 3-1 win last August.
He started his career with Rotherham United and after making an impression moved to Watford in January 2007 - along with Lee Williamson after a five year spell with the Millmoor side. In July 2010 he joined Bristol Rovers and during his spell at Vicarage Road spent time out on loan at Millwall at Nottingham Forest.
United completed the deal ahead of today's 11pm transfer deadline.