What is the term for an imperfection that does not impact the usefulness of a horse?

The term "blemish" specifically refers to an imperfection on a horse that does not significantly affect its performance or utility. Blemishes are typically cosmetic issues, such as superficial scars or minor skin blemishes, that do not interfere with the horse's abilities or overall health. This differentiates blemishes from more serious defects or flaws, which can impact the horse’s usability in various disciplines.

In contrast, a defect often implies a more serious problem that can affect the horse's physical capabilities or overall functionality, while a flaw may encompass a broader range of imperfections that could influence performance. The term "condition" generally pertains to the overall health or status of the horse rather than specific imperfections. Therefore, "blemish" is the most appropriate term to describe an imperfection that does not hinder the horse's usefulness.