The late great comedian Norm Macdonald commented: “ID… there’s a strange abbreviation when you think about it. ‘I’ is short for ‘I,’ and then ‘D’ is short for dentification.'”
Macdonald wasn’t quite right with his assessment, but he was correct in that some abbreviations can be more confusing than they are helpful. If you can’t decipher what an abbreviation stands for, should the word or phrase be shortened at all? Even everyday terms may boggle the mind: For example, why is “pound” abbreviated as “lb”? Maybe you memorized the term in school, or maybe one day you asked the deli manager what that “LB” on the sticker meant, but it’s not an easy one to decipher on its own, because the word and its abbreviation don’t share a single letter. There is an answer as to why it’s shortened that way, though, and it dates back to ancient Rome.
The Romans used a basic unit of weight called a libra (~0.722 pounds), derived from the Latin for “scale” or “balance.” Libra pondo is a Latin phrase that translates to “a pound by weight.” When these terms reached Britain, they became the standard for weighing gold and silver. The abbreviation “lb” is a shortening of libra that was carried over to the English word “pound.” The British currency is also called the pound, and the £ symbol represents libra.
Another concept worth mentioning is the Roman uncia, a Latin word that translates to “one-twelfth.” It was used by the Romans as a unit of measurement for one-twelfth of a libra, and it became the inspiration for the English word “ounce.” So, where did that “z” in the abbreviation “oz” come from? On the journey from Latin to English, there was a detour with the Italian word onza.