Gerund noun: the act or process of moving rapidly downward in a sweeping motion.
Definitions
The action or process of moving rapidly downward through the air in a sweeping motion. The owl's silent swooping startled its prey.
swoopgerund / present participle Added because the present participle "swooping" is frequently used attributively (e.g., "a swooping bird").
Definitions
Moving swiftly downward or forward in a sweeping motion. The swooping hawk circled above the field.