When someone says the phrase “something or other really gets my goat,” they mean that they are extremely irritated. A wide variety of things could contribute to irritation, ranging from someone else's actions to a series of events, but, despite the turn of phrase, goats are not usually involved. Like many colorful idioms in the English language, the origins of “get my goat” are murky, difficult to pin down, and actually rather fascinating, for people who enjoy exploring language.

The first incidences of the phrase crop up around the early 1900s, and seem to suggest that this idiom is American in origin. The early 1900s were, in fact, a great era for colorful slang terms in America, reflecting the rapid expansion of settlement in the United States and the commingling of people from a wide variety of social, class, and ethnic backgrounds. A number of slang terms from this era are undoubtedly corruptions of slang from other languages, or misunderstandings of English words, and some people have suggested that “gets my goat” may be related to “goad,” as in “to irritate.”

However, this mundane explanation has been eclipsed by a number of other interpretations of the slang term. Others have suggested that the term is a translation from the French prendre la chèvre, “to take the goat,” an idiom from Old French which references taking someone's form of income. For low-income French peasants, the theft or a goat would be a catastrophe, as the animals provided milk and meat for their owners. However, this explanation may be a backformation to explain "gets my goat," rather than a true explanation of the origins of the phrase.

One of the most likely explanations behind “gets my goat” is also one of the more interesting, something which rarely happens when exploring the roots of common idioms. As early as the 1700s, goats were used as companion animals to help settle race horses, keeping the notoriously skittish animals relaxed. Taking a horse's pet goat away would have agitated and upset the animal, potentially influencing the outcome of a race.

The practice of providing race horses with companion animals is still widespread, with horses bonding with ponies, chickens, dogs, cats, and a variety of other animals in addition to goats. Many horses do indeed become deeply attached to their companions, exhibiting considerable stress when these animals are removed, and this behavior could have inspired the idiom “gets my goat” among observers.