fast

The word "fast" may look simple, but it has several common meanings. Most often, it means moving at high speed, like a fast car or a fast runner. It can also describe something that happens quickly, such as a fast response or a fast learner.

But that is not the whole story. In phrases like "hold fast," it means to keep a firm grip or stay strong. And if a doctor tells you to "fast" before a test, they mean that you should not eat for a period of time. The meaning depends on the situation.

The word "fast" primarily describes speed or the rate at which something happens. A cheetah is a fast animal, and information travels at a fast pace across the internet. We use it to describe anything in motion: a fast train, a fast current, or a fast-paced lifestyle. Beyond physical movement, it can refer to time—a fast week seems to fly by—or efficiency, such as a fast typist or a fast reader.

Interestingly, "fast" also has an older meaning related to firmness and stability. In this sense, it means "firmly fixed" or "secure." This usage survives in phrases such as "hold fast," which means to keep a strong grip or remain faithful to an idea or purpose. In older or literary use, it can also describe something that stays firm and does not come loose easily.

Furthermore, "fast" can function as a noun or a verb in connection with food. A "fast" is a period of not eating, often for religious, medical, or health reasons, and to "fast" means to go without food for that time. It also appears in technical language about color: "fast colors" are colors that do not fade or wash out easily. From speed and quick action to firmness and not eating, "fast" changes meaning with the context around it.