Horse terminology just as bad!
Horse can be a stud horse (male), but male horses are generally called colts up to 5 yrs of age, or stud colt if not gelded.
Once gelded is is gelding no matter the age.
Males over 5yrs are called stallions.
Mares are over the age of 5yrs? And under 5 they are fillies. Even if they produce a foal.
A foal covers both male (colt) and females (filly). Foals are under 1 yr of age.
Yearlings are either colts or fillies
Personally I just call them all hay burners and lawn ornaments!
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