Swiftness is a term used to describe the state of being quick, speedy and agile. However, there are a plethora of synonyms that can be used in place of swiftness to add variety to your writing and speech. Some of the common synonyms for swiftness are rapidity, celerity, fleetness, alacrity, hastiness, expeditiousness, velocity, acceleration, quickness, and fastness. Each of these terms encapsulates the idea of speed and agility and can be used in different contexts and scenarios. By using these synonyms, you can add depth and nuance to your writing and avoid repeating the same term multiple times.