Pronunciation: [bˈɪli͡ənθ] (IPA) 
The word "billionth" is spelled with two syllables, "bil" and "lionth." The first syllable, "bil," is pronounced like the word "bill" with a short i sound. The second syllable, "lionth," is pronounced like "lye-onth." The stress in this word falls on the second syllable, which is common in words ending in "-th." "Billionth" is often used to refer to the ordinal number that follows a billion, indicating a position of one billionth.
The term "billionth" refers to the ordinal number that represents the position of a particular element in a sequence consisting of one billion (1,000,000,000) parts. It is derived from the word "billion," which signifies the number one followed by nine zeros. As an adjective, "billionth" describes something that occupies the position of number one billionth in a series.
In mathematical terms, "billionth" is equivalent to dividing a whole into one billion equal parts. It has a value of 1/1,000,000,000 or 1 divided by 1 billion. This fraction implies that a billionth is an incredibly small unit, making it an essential concept in fields where precise measurements and calculations are necessary, such as physics, chemistry, and economics.
The term "billionth" can also be used as a noun to represent an individual item or element in a series. For example, in a sequence of one billion numbers, the billionth number refers to the number that occupies the final position in the sequence. Similarly, in an ordered set or list of one billion objects, the billionth object is the last item on the list.
Overall, "billionth" signifies an infinitesimally small proportion or position within a series composed of one billion components, playing a vital role in quantifying and distinguishing elements in various numerical and ordered contexts.
The word "billionth" is derived from the combination of two elements: "billio", which corresponds to the number "one billion", and the suffix "-th", which is used to form ordinal numbers.
The term "billion" originated from the French word "billion", which was introduced in the 15th century. In Old French, "bi-" meant "two" and "-llion" was derived from the word "milion", representing "one million". The term "billion" denoted "two (bi-) millions", or 1,000,000,000 (1 billion) in the modern numeric system.
When combining "billion" with the "-th" suffix, it forms "billionth", which specifically signifies the numerical position of one in a billion.
