I remember a song by a French singer Jean-Louis Aubert titled “Milliers, Millions, Milliards”, translated as “Thousands, Millions, Billions” in English. While a rather catchy song in its melody and lyrics, the title alone sort of hides a little linguistic curiosity.

Let’s explore another example, using a different language branch. In German, “million” is, well, “Million”, but “billion” is translated as “Milliarde”, while “trillion” is translated as “Billion”. Strange.

Let’s try another language that is somewhat close to English — Frisian or Dutch. Respectively, “million, billion, trillion” is translated as “miljoen, miljard, triljoen”. Even more distantly related languages in Europe like Finnish follow a similar pattern “miljoona, miljardia, triljoona”. This brings us to this question: Why is “billion” in English known as something like a “milliard”, and in some languages, “trillion” known as a “billion”?

It turns out, the answer is quite interesting, so stick around.

The word “billion” did not always carry the meaning of “one billion” or “one thousand million” in English. In fact, until 1974, the British used the word “milliard” in rare occasions to carry the meaning of “one thousand million”, while the Americans simply used the word “billion” instead. While there is no longer any distinction between the British and the American usage of the word “billion” today, it is quite cool to note that the Americans never quite used the word “milliard” before.

A deeper dive takes us into this thing known as long and short scales. These scales show the two distinct systems of how we name integer powers of 10. The two scales are quite identical for whole numbers smaller than 1,000,000,000 (one thousand million, or one billion). But from then on, this is where the systems diverge.

The long scale interestingly proceeds by powers of one million, while the short scale proceeds by powers of one thousand. For example, one million million is known in the short scale as a “trillion”, but in the long scale, it is a “billion”. In the long scale, however, each intervening “thousand” step carries the ending -ard, leading to words like “trilliard” being possible (meaning one sextillion in the short scale, or 10^21).

Most English-speaking countries today use the short scale, ie. one billion is 10^9. This change was probably prompted by the UK, which switched from a more ambiguous thing to the short scale, given the report in 20 December 1974:

“Mr. Maxwell-Hyslop asked the Prime Minister whether he would make it the practice of his administration that when Ministers employ the word ‘billion’ in any official speeches, documents, or answers to Parliamentary Questions, they will, to avoid confusion, only do so in its British meaning of 1 million million and not in the sense in which it is used in the United States of America, which uses the term ‘billion’ to mean 1,000 million.

The Prime Minister: No. The word ‘billion’ is now used internationally to mean 1,000 million and it would be confusing if British Ministers were to use it in any other sense. I accept that it could still be interpreted in this country as 1 million million and I shall ask my colleagues to ensure that, if they do use it, there should be no ambiguity as to its meaning.”

Across the last quarter of the 20th century, many other countries switched, or stated officially, the use of the short scale in the English language, although some countries still retain an ambiguity about the official status of the short scale, or use the long scale in some regions or areas.

Another prominent language that uses the short scale is Arabic, with most regions and countries using it, but with a little difference from English: instead of 10^9 being something like billion, most of these countries use milyar مليار, and 10^12 being tirilyoon تريليون. Note that in countries like Saudi Arabia and the UAE, بليون billion for 10^9 is used.

Continental Europe is probably the place where one would find languages generally using the long-scale, especially in languages like French, Spanish, German, and Dutch. Italy also confirmed its use of the long scale in 1994. So in languages like these, one would hear something like million for 10^6, milliard or the equivalent of one thousand million for 10^9, and billion for 10^12.

Of course, there are languages that use neither the long nor short scale. Traditional systems, or traditional myriad systems based around 10,000 may be used, and so they do not quite fit the description for either short or long scale. Interestingly, Mongolian has special words in its traditional myriad system for numbers up to 10^67, despite us probably almost never using numbers like these in our lives. Another example includes the countries of India, Pakistan, and Bangladesh, which use the lakh, crore, and arab to denote 10^5, 10^7, and 10^9 respectively.

I hope this clears some confusion around the use or translation of million, billion, and trillion (short scale here) in various languages that may use the long scale, short scale, of neither. While the deep history of such numerical terms were not really covered, it is interesting to note some patterns of usage in some languages around the world.