myriad

The indefinite number myriad is first recorded in English in 1555, but its usage begins much longer ago. English borrows it, via both French then Latin, from Ancient Greek μυριάς (muriás), meaning “ten thousand”. μυριάς is in turn derived from μυρίος (muríos), meaning “countless”. So we find ourselves in the current situation where the English word can mean either number based on context.

Besides Greek, I find myself using the 10,000 meaning most often around CJK media, as instead of words for 10^3 and its powers, those langauges use words for 10^4 and its powers. I find myriad to be a natural gloss for 10^4. Notably, my parents have lived in the US for over fifty years yet still think in myriads, so I often have to translate large numbers back and forth.

This was most salient to me when I was into a Japanese Dreamcast proto-bullet hell shooter in the early 2000s that naturally used 10^4 for its digit separators. I knew I could easily tell what my score was once it was above one trillion (10^12), because I could anchor on the separator at one cho (10^12).

The other commonly used digit grouping is the Indian system, which in addition to thousand has words for 10^5, lakh, 10^7, crore, and every subsequent set of 10^2. To sum up, when internationalizing large integers you’d ideally use the following formatting:

US English: trillion = 1,234,567,890,123 Japanese: 兆 (cho) = 1,2345,6789,0123 Hindi: लाख करोड़ (lakh crore) = 12,34,56,78,90,123 French: billion = 1 234 567 890 123 German: Billion = 1.234.567.890.123

Isn’t it convenient that we all use Arabic numerals?

…what do you mean these aren’t the numerals people use in written Arabic?