No, a nodachi is not considered a type of katana. While both the nodachi and katana are Japanese swords, they have distinct characteristics that differentiate them from each other.

Nodachi:

The nodachi, also known as ōdachi, is a large two-handed sword from Japan. It features an exceptionally long blade, typically measuring around 90 centimeters (35 inches) or longer. The nodachi was primarily used by warriors on foot and was designed for combat against cavalry or in open-field battles. Due to its size and weight, it required both hands to wield effectively.

Katana:

The katana, as mentioned earlier, is a more well-known and iconic Japanese sword. It has a curved, single-edged blade with a typical length ranging from around 60 to 75 centimeters (24 to 30 inches). The katana was the primary weapon of the samurai class and was used for a wide range of combat techniques. It was designed for versatile use, combining cutting power, maneuverability, and the ability to be worn with the cutting edge facing down.

While both the nodachi and katana are traditional Japanese swords, the main distinction lies in their size and intended use. The nodachi is a much larger weapon designed for specific combat situations, while the katana is a more versatile and commonly used sword by samurai warriors.