A saber is a type of sword that is defined by several distinctive features:

1. Curved Blade: A saber typically has a curved blade that forms an arc along its length. The curve can vary in degree and may be more pronounced towards the tip or evenly distributed along the blade.
2. Single Cutting Edge: Sabers typically have a single cutting edge, meaning that only one side of the blade is sharpened. This allows for efficient slashing and cutting motions.
3. Handguard: Sabers often have a handguard or hilt that is designed to protect the user's hand. The handguard can take various forms, such as a cup-shaped guard, a swept hilt, or a knuckle bow, depending on the specific style and design of the saber.
4. Grip and Pommel: Sabers have a handle or grip where the user holds the sword. The grip is usually long enough to accommodate a single hand or a hand and a half. The pommel, located at the end of the grip, serves as a counterweight and helps to balance the sword.
5. Designed for Slashing: The curvature of the saber's blade, combined with its single cutting edge, makes it well-suited for slashing and cutting attacks. Sabers are optimized for delivering powerful and precise strikes.

While these features generally define a saber, it's important to note that there can be variations in design across different cultures, time periods, and individual swords. The term "saber" can encompass various styles and types of swords that share these defining characteristics.