The loss snapped the Terps' 20-game Big Ten win streak.
The Terps are still searching for consistency entering the last month of the regular season.
Libby May, Eloise Clevenger and Hannah Leubecker all scored hat tricks in the Terps' win over the Tigers.
The Terps held the Nittany Lions scoreless for more than 26 minutes in the second half.
The Terps allowed just two goals in the second half to win its first conference game of the season.
Chrissy Thomas led the Terps with seven points and was part of a second-half seven-goal run.
Bosco transferred to the Terps from the Quakers and will play at her former home field on Wednesday.
Daniel Kelly scored the game-winner to hand the Cavaliers their first loss of the season.
Hannah Leubecker led the charge with five first half goals.
The Terps beat the Cavaliers in the NCAA tournament quarterfinals last season.