A stable supply is a consistent and reliable source of goods or services. The term can be broken down into three parts: FED (3 letters), HAY (3 letters), and OATS (4 letters). Fed refers to the practice of providing livestock with food, HAY is a type of grass used as animal feed, and OATS are a type of grain also used as animal feed. Together, these three components make up a stable supply of food for animals.