An SI prefix is a prefix, that, when applied to a word, means to multiply that word by a particular power of ten.[1] Examples of applications of SI prefixes include kilometer, megapixel, and gigabyte. These prefixes are often applied to units of measurement.
Prefixes
The standard large and small SI prefixes are given below.
Name | Value | Factor/Divider | Name | Value |
---|---|---|---|---|
deca- | 10 | ten | deci- | 0.1 |
hecto- | 100 | hundred | centi- | 0.01 |
kilo- | 1000 | thousand | milli- | 0.001 |
mega- | 106 | million | micro- | 10-6 |
giga- | 109 | billion | nano- | 10-9 |
tera- | 1012 | trillion | pico- | 10-12 |
peta- | 1015 | quadrillion | femto- | 10-15 |
exa- | 1018 | quintillion | atto- | 10-18 |
zetta- | 1021 | sextillion | zepto- | 10-21 |
yotta- | 1024 | septillion | yocto- | 10-24 |
Etymology
SI stands for "Système international", French for "international system"[2].
Extensions
Andre Joyce's extension
Andre Joyce fabricated an extension to the system,[3] noting that zetta and yotta seem related to sette (Italian "seven") and otto (Italian "eight.") Following the reverse-alphabet pattern, we have xova- \(= 10^{27}\), x + nove, and weica- \(= 10^{30}\), w + dieci. (The last letter has been changed to a to keep the pattern.) The pattern for the corresponding negative exponents, like deci-, centi-, and milli-, all end in -i.
From here, only the first syllable of the Italian number is used. We have:
- vunda- = \(10^{33}\), v + und(ici), vundi- = \(10^{-33}\)
- uda- = \(10^{36}\), u + (do)d(ici), udi- = \(10^{-36}\)
- treda- = \(10^{39}\), t + tred(ici), tredi- = \(10^{-39}\)
- satta- = \(10^{42}\), s + (qu)att(ordici), satti- = \(10^{-42}\)
- rinda- = \(10^{45}\), r + (qu)ind(ici), rindi- = \(10^{-45}\)
- qeda- = \(10^{48}\), q + (s)ed(ici), qedi- = \(10^{-48}\)
- pica- = \(10^{51}\), p + (d)ic(iasette), pici- = \(10^{-51}\)
- oca- = \(10^{54}\), o + (di)c(iotto), oci- = \(10^{-54}\)
- nica- = \(10^{57}\), n + (di)c(iannove), nici- = \(10^{-57}\)
- menta- = \(10^{60}\), m + (v)ent(i), menti- = \(10^{-60}\)
The system continues to zotta- = \(10^{255}\) and zotti- = \(10^{-255}\).
Jim Blowers' extension
Initially Jim Blowers, like Andre Joyce, followed reverse-alphabet pattern and extends his system up to vigintillion:
- xona- = 1027
- weka- = 1030
- vunda- = 1033
- uda- = 1036
- treda- = 1039
- sorta- = 1042
- rinta- = 1045
- quexa- = 1048
- pepta- = 1051
- ocha- = 1054
- nena- = 1057
- minga- = 1060
- luma- = 1063
However, recently he changed this system and proposed his own system of prefixes up to 103,000. Here is a list of his prefixes:[4]
- nina- = 1027
- tena- = 1030
- tenakilo- = 1033
- tenamega- = 1036
- tenagiga- = 1039
- tenatera- = 1042
- tenapeta- = 1045
- tenaexa- = 1048
- tenazetta- = 1051
- tenayotta- = 1054
- tenanina- = 1057
- bitena- = 1060
- bitenakilo- = 1063
- quadtena- = 10120
- huna- = 10300
- tousa- = 103,000
Hella-extension
Austin Sendek, a University of California student, started a (somewhat jocular) Facebook petition to make "hella-" the official SI prefix for 1027.[5][6] "Hella" is a slang term originating out of Northern California, meaning "a lot of" or "very". The term has not become official, but both Google and Wolfram|Alpha have adopted it into their calculator systems.[7]
Other extensions
There are many other extensions to the SI prefixes, which are listed on the wiki's articles on extended SI prefixes - for example, see the article Prefix 1027.
Sources
See also
Suffixes: -teen · -ty · -plex · -illion · -yllion · -exian · -chime · -toll · -gong · -bong · -throng · -illiob
Prefixes: gar- · fz- · fuga- · megafuga- · booga- · trooga- · googo- · googolple-
SI prefixes: deca- · hecto- · kilo- · mega- · giga- · tera- · peta- · exa- · zetta- · yotta-
Obsolete SI prefixes: myria-
Extended SI prefixes: 1.001 · 1.01 · 1.1 · 1.5 · 2 · 3 · 666 · 105 · 107 · 108 · 1010 · 1011 · 1013 · 1014 · 1016 · 1017 · 1019 · 1020 · 1022 · 1023 · 1025 · 1027 · 1028 · 1029 · 1030 · 1031 · 1032 · 1033 · 1034 · 1035 · 1036 · 1039 · 1042 · 1045 · 1048 · 1050 · 1051 · 1054 · 1057 · 1060 · 1063 · 1066 · 1069 · 1072 · 1075 · 1078 · 1080 · 1081 · 1084 · 1087 · 1090 · 10100 · 10120 · 10150 · 10180 · 10210 · 10240 · 10270 · 10300 · 10600 · 10900 · 101200 · 101500 · 101800 · 102100 · 102400 · 102700 · 103000 and higher