# xenna-

Definition from Wiktionary, the free dictionary

## English[edit]

### Etymology[edit]

Ancient Greek *ἐννέα* (ennéa, “nine”), for the ninth order of 10^{3}, and the letter *x*, as the third term in a series running backwards through the alphabet (after *zetta-* and *yotta-*). The final *a* conforms to the final vowel of the SI series from mega- upwards.

### Pronunciation[edit]

### Prefix[edit]

**xenna-**

- (neologism) In metric systems of units, multiplying the unit to which it is attached by 10
^{27}; octillion-. 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) (10^{27}), or vendeko (v) (10^{-33}) and vendeka (V) (10^{33}) exist, and can help simplify the expression of extreme numbers.

- The SI prefixes above are not the only extreme ones. Others such as xenno (x) (10
**1997**, Council of Scientific & Industrial Research,*Science Reporter*Vol. 34, page 23:- If we try to calculate the mass of earth it comes to 6
**xenna**grams which is nothing but 6x10^{24}kilograms or 6x10^{27}gms.

- If we try to calculate the mass of earth it comes to 6
**2015**, Claude Phipps,*No Wonder You Wonder!: Great Inventions and Scientific Mysteries*, Springer, page 62:- But that's nothing: our universe is about 0.8 Xm (
**Xenna**metres, billions of billions of billions of metres) in diameter.

- But that's nothing: our universe is about 0.8 Xm (
- For more examples of usage of this term, see Citations:xenna-.

#### Derived terms[edit]

#### Usage notes[edit]

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