xenno-

English

Etymology

From Ancient Greek ἐννέα (ennéa, “nine”), for the ninth order of 10³; with the letter x added for the third term in a series running backwards through the alphabet (after zepto- and yocto-). The final o conforms to the final vowels of the SI series from micro- downwards.

Prefix

xenno-

1. In metric systems of units, multiplying the unit to which it is attached by 10^-27. Symbol: x
   • 1994, IPC Magazines, New Scientist Vol. 144, page 81:

     The SI prefixes above are not the only extreme ones. Others such as xenno (x) (10^-27) and xenna (X) (10²⁷), or vendeko (v) (10^-33) and vendeka (V) (10³³) exist, and can help simplify the expression of extreme numbers.

   • 2002, Greg Egan, Schild's Ladder, Gollancz (2008), page 184:

     'Now we're talking xennobiology!' [...] a complex organism based on similar processes to the primitive ones they'd seen probably would be about a xennometre in size.

   • 2004 November, Seth Lloyd, Y. Jack Ng, "Black Hole Computers", Scientific American, page 56:

     From Nanotech to Xennotech [...] A one-kilogram hole has a radius of about 10^-27 meter.

Usage notes

Not a standard prefix in the metric International System of Units.

Antonyms

• xenna-

Anagrams

• xenon