What is the proper term for a young horse less than six months old?

The term "foal" specifically refers to a young horse that is less than six months old. This designation applies to both male and female young horses prior to the age of weaning. After this age, they may be referred to as a colt if they are male or a filly if they are female, but while they still fall under the category of being less than six months old, they are termed foals. Understanding this distinction is important for anyone involved in horse breeding and care, as it provides clarity in age classification and the developmental stage of the horse.

In contrast, the other terms relate to different age classifications or genders; a colt specifies a male horse that is less than four years old, a filly refers to a female horse under the same age range, and a pony is a breed classification based on height, not age. Thus, recognizing the correct terminology regarding young horses allows for better communication and understanding within the equine community.