Hinney is an uncommon term that is rarely used in everyday conversation. However, if you need to find a suitable synonym, there are options available. The term "hinny" refers to a female mule, a hybrid animal that is the result of breeding a male horse with a female donkey. Some synonyms for the word "hinney" include "mule," "donkey," "jackass," and "jenny." These terms are more commonly used and may be more familiar to people. Additionally, the terms "hybrid" or "crossbreed" could also be used to describe the offspring of a horse and donkey.