When you use the phrase "under my belt," it can have multiple meanings. You may be using it to explain you have acquired or possess experience in a particular area. For example, you might say, "I'm an expert at knitting now that I have five years of practice under my belt." However, it can also reference something you have consumed, like food or drink.

Drink Up!

The earliest usages of the phrase "under my belt" appear in literature, and primarily reference the consumption of alcohol. For example, in "Ormond, A Tale," by Maria Edgewort, written in 1873, a character had a rule of never going to bed "without a proper quantity of liquor under this belt." In "The Miscellaneous Works of Tobias Smollett, M.D," published in 1790, the author states that a man was carried home with "bottles of claret under his belt." Claret is a type of red wine.

Ownership

There are few earlier references of the phrase "under my belt" as it refers to owning something or possessing knowledge. One early reference is found in a Scottish proverb, which claims, "Your tongue is not under my belt," meaning that a person cannot make you be quiet.