The word "hundred" is so commonplace in English that most people never stop to consider its origins or its original meaning. Interestingly, despite its current definition as a cardinal number equal to 10 times 10, the etymology of "hundred" reveals a complex history and a significant shift in numerical value over the centuries.
Tracing its roots back to the Old Norse word "hundrath," the term originally described a unit of 120, not 100. This can be somewhat confusing since the component parts of the word, "hund-" and "-rath," suggest a different story. "Hund-" corresponds closely to the English word "hundred," but "-rath" is a less familiar element that indicates a reckoning or count. This format of counting or grouping items by 120 is known as the "long hundred" or "great hundred," primarily used in ancient counting systems for trade and inventory purposes.
This usage is not unique to Norse cultures; similar concepts existed among other Germanic peoples. The long hundred was used extensively across Northern Europe and is thought to be influenced by the base-12 counting systems, which were prevalent in many ancient cultures due to the divisibility of 12 (having multiple divisors: 1, 2, 3, 4, 6). The practical applications of using 120 as a base unit in trade or goods counting made arithmetic calculations simpler and more straightforward in a pre-decimal era.
The shift from 120 to 100 as the accepted value of a hundred is a bit murky in historical documentation, but it is believed to be connected to the introduction and standardization of the decimal system, along with its broader acceptance which favored base-10 calculations. The move towards a simplified base-10 system, which aligns with the SI units of measurement used globally today, marked the phasing out of the long hundred in regular usage.
Understanding this historical shift offers not just a linguistic or numerical curiosity but also highlights the fluid nature of language and math as they adapt to cultural and practical necessities. The evolution from 120 to 100 in the definition of "hundred" is a perfect example of how practical needs, along with cross-cultural exchanges, shape the words and numbers we use every day. Such shifts in language and measurement systems underline the dynamic, ever-evolving nature of human communication and computation.
