Which form of maneuver is characterized by attacking an enemy from the side?

The form of maneuver characterized by attacking an enemy from the side is known as a Flank Attack. This tactic is effective because it targets the enemy's less fortified sides, often catching them off guard and disrupting their organization. A flank attack can exploit gaps in the enemy's defense, allowing for a better chance of success in gaining a tactical advantage.

In contrast, a Frontal Attack involves direct engagement with the front of the enemy's position, which often results in higher casualties due to the confrontation of well-prepared enemy defenses. A Turning Movement seeks to bypass the enemy's frontline and strike at their rear or flanks, but it does not specifically define the engagement with the enemy's side directly as a Flank Attack does. Infiltration refers to a stealthy movement through enemy territory to gather intelligence or make contact without direct engagement, which is a different tactical approach altogether.

Thus, the definition and execution of a Flank Attack make it the correct choice for a maneuver that specifically involves attacking an enemy from their side.