There exist several unofficial SI prefixes, known as "bogus" SI prefixes. Some of these were proposals that were rejected. None are in common use, and many of the powers of ten they represent are already taken by official prefixes. In addition, the SI prefixes myrio and myria are obsolete.
One such bogus prefix is bronto, used in the fake term brontobyte. References on the World Wide Web suggest meanings of the bronto prefix to be variously any of 1015, 1021, 1024, or 1027. SI has already produced standard prefixes for 1015 (peta), 1021 (zetta) and 1024 (yotta).
There are many other unofficial prefixes. Some of them appear to come from a numerical Greek root indicating the power of 1000 the prefix means. These prefixes are as follows:
| Prefix
| Purported meaning
|
| una
| 1033
|
| vendeka (V)
| 1033
|
| weka (W)
| 1030
|
| dea
| 1030
|
| nea
| 1027
|
| xenna (X)
| 1027
|
| otta
| 1024
|
| hepa
| 1021
|
| ento
| 10-21
|
| fito
| 10-24
|
| syto
| 10-27
|
| xenno (x)
| 10-27
|
| tredo
| 10-30
|
| weko (w)
| 10-30
|
| revo
| 10-33
|
| vendeko (v)
| 10-33
|
Higher and lower orders of magnitude
It has been proposed [Shuch, H. Paul, The large and the small of it (Letter). Science News 143(14): 211, April 3, 1993] to extend the scale in both directions, by continuing to work backward through the alphabet. Thus 10-27 becomes xocto, 10-30 becomes wocto, etc., through to acto (10-96). Similarly, 1027 becomes xotta, 1030 becomes wotta, etc., clear through to atta (1096).
External links
