English has gender specific terms "colt" for a young stallion and "filly" for a young mare. Polish has a gender-neutral term "zrebie", of which "zrebak" is a derivative. Thus, even though the grammatical gender of "zrebak" is masculine, it does not necessarily indicate a male animal. Horse breeders will use "ogierek" and "klaczka" for "colt" and "filly".

No references; personal experience as a rider/"horsy person"|.