Brazil is home to a rich diversity of primates. The idea of a monkey on a horse plays into the fear of nature "turning the tables" on humanity. The horse is a symbol of human domestication and civilization; the monkey is a symbol of wild nature. The Macaco Hípico represents the intrusion of the wild into the civilized domain, implying that nature can adopt human tools (horses, clothes) to terrorize humans.
Often used colloquially in sports to denote agility or a specific "character" within the community. macaco hipico
For accurate information, please provide additional context (e.g., where you saw or heard the term, language region, or associated image). Brazil is home to a rich diversity of primates