Moorhouse, who represents the Republic of Ireland at the Under-21 level, will join the team for the current year.
Orient's manager, Richie Wellens, expressed his enthusiasm for the signing, saying that Moorhouse is an extremely talented footballer.
Wellens, a former junior player at Manchester United himself, believes that Moorhouse has the ability to significantly impact the game with his playing style.
The manager is excited about the potential of this signing, stating that Moorhouse has a lot to offer the team.