Cat's-tail is a term that refers to a type of long, slender grass with fluffy seed heads that resemble the tail of a cat. Other synonyms for cat's-tail include timothy grass, meadow foxtail, and water foxtail. Timothy grass is a popular grass that is commonly used for hay and pasture. Meadow foxtail is a species of grass that is native to Europe and is commonly used for forage. Water foxtail is another type of grass that grows in wet areas and is often used for erosion control and water purification. While these grasses may have different names, they all share the common characteristic of having fluffy, cat-like seed heads.