👉 Fluid, in this context, refers to a state or substance that exhibits properties of both liquids and gases. It can flow like a liquid but also expand to fill its container much like a gas does, adapting its shape to conform to any container it's placed in. This unique characteristic allows fluids to exhibit behaviors such as spreading out when exposed to a larger surface area, rising in narrow tubes due to capillary action, and easily taking the shape of their environment. Examples of fluids include water, air, and many gases.