{
  'googol' => [%w{googol},             1e100],
  'yobi'   => [%w{Yi Yobi yobi},       2**80],
  'zebi'   => [%w{Zi Zebi zebi},       2**70],
  'exbi'   => [%w{Ei Exbi exbi},       2**60],
  'pebi'   => [%w{Pi Pebi pebi},       2**50],
  'tebi'   => [%w{Ti Tebi tebi},       2**40],
  'gibi'   => [%w{Gi Gibi gibi},       2**30],
  'mebi'   => [%w{Mi Mebi mebi},       2**20],
  'kibi'   => [%w{Ki Kibi kibi},       2**10],
  'yotta'  => [%w{Y Yotta yotta},      1e24],
  'zetta'  => [%w{Z Zetta zetta},      1e21],
  'exa'    => [%w{E Exa exa},          1e18],
  'peta'   => [%w{P Peta peta},        1e15],
  'tera'   => [%w{T Tera tera},        1e12],
  'giga'   => [%w{G Giga giga},        1e9],
  'mega'   => [%w{M Mega mega},        1e6],
  'kilo'   => [%w{k kilo},             1e3],
  'hecto'  => [%w{h Hecto hecto},      1e2],
  'deca'   => [%w{da Deca deca deka},  1e1],
  '1'      => [%w{1},                  1],
  'deci'   => [%w{d Deci deci},        Rational(1,1e1)],
  'centi'  => [%w{c Centi centi},      Rational(1,1e2)],
  'milli'  => [%w{m Milli milli},      Rational(1,1e3)],
  'micro'  => [%w{u µ Micro micro mc}, Rational(1,1e6)],
  'nano'   => [%w{n Nano nano},        Rational(1,1e9)],
  'pico'   => [%w{p Pico pico},        Rational(1,1e12)],
  'femto'  => [%w{f Femto femto},      Rational(1,1e15)],
  'atto'   => [%w{a Atto atto},        Rational(1,1e18)],
  'zepto'  => [%w{z Zepto zepto},      Rational(1,1e21)],
  'yocto'  => [%w{y Yocto yocto},      Rational(1,1e24)]
}.each do |name, definition|
  RubyUnits::Unit.define(name) do |unit|
    aliases, scalar = definition
    unit.aliases    = aliases
    unit.scalar     = scalar
    unit.kind       = :prefix
  end
end