The 20-year-old has linked up with the League One outfit for the remainder of the current campaign, and could make his Grecians debut in their home game against Forest Green Rovers a week on Saturday.
Carlisle-born White has been on the fringes of the Magpies' first team this season, appearing for Eddie Howe's side during their Diriyah Cup win over Al Hilal in Riyadh last month.
He has been a regular in United's under-21 side, too, scoring three goals and registering one assist in 14 outings for Newcastle's second string so far this term.
White also spent time out on loan at Hartlepool United in 2021/22, where he made 16 appearances and provided three assists during his first temporary stint away from St. James' Park.
Exeter, who are managed by former Newcastle player and coach Gary Caldwell, currently sit tenth in the third tier.