filly

A filly is a young female horse that has not yet become a mare. In simple terms, all baby horses are foals at first, but as they grow, a young male is called a colt and a young female is called a filly. You will often see this word in horse racing, farming, and stories about the countryside. A well-known race for three-year-old fillies is the Kentucky Oaks.

Think of it this way: foal is the general word, colt is for a young male, and filly is for a young female. When she grows up, she becomes a mare. In older writing, the word could also mean a lively young woman, but that use is now uncommon.

The word "filly" refers to a young female horse, usually one that has not yet fully matured into a mare. In everyday understanding, it is the female match for "colt." Very young horses are first called foals, and later the words "colt" and "filly" help show whether the young horse is male or female. The exact age limit can vary a little by context, but in racing and horse care it often refers to a female horse under four or sometimes under five years old.

You will most often meet this word in horse racing, breeding, and general talk about horses. Races may be limited to fillies, and sales or breeding records may also use the term because sex and age matter in those settings. A famous example is the Kentucky Oaks, a major American race for three-year-old fillies. Outside racing, the word can describe any young female horse in a field, on a farm, or in a stable.

The word has also been used in older or literary English for a lively young woman, sometimes with a playful tone. That meaning is now old-fashioned and much less common than the horse sense. Most of the time, if you see "filly" today, it simply means a young female horse, with a feeling of youth, energy, and growing strength.