The origin of femto, atto and zepto SI prefixes Do you know why the SI prefixes: femto, atto, zepto have been accepted by Scientific Community, if this triad of metric units, is neither greek nor latin?
 A: From http://www.exa.com.au/metric/ a rewrite of the NIST Constants, Units & Uncertainty home page 
Prefixes ranging from micro to mega were first introduced in 1874 by BAAS as part of their CGS system. Later, 12 prefixes ranging from pico to tera were defined as part of the International System of Units - SI, which was adopted in 1960. SI is maintained by BIPM under exclusive supervision of CIPM and resolutions made by CGPM. Further 8 prefixes were added to SI in years 1964 (femto, atto), 1975 (peta, exa) and 1991 (zetta, zepto, yotta, yocto). 
exa alteration of hexa from Greek hex meaning "six" (the sixth power of 10^3)
peta    alteration of penta from Greek pente meaning "five" (the fifth power of 10^3)
tera    from Greek teras meaning "monster" 
giga    from Greek gigas meaning "giant" 
mega    from Greek megas meaning "great" 
kilo    from Greek khilioi meaning "thousand" 
hecto   French, alteration of Greek hekaton meaning "hundred"
deca    from Greek deka meaning "ten"
deci    from Latin decimus meaning tenth, from decem meaning "ten"
centi   from Latin centi-, from centum meaning "hundred"
milli   from Latin mille meaning "thousand" 
micro   from Greek mikros meaning "small"
nano    from Greek nannos meaning "dwarf" 
pico    from Spanish pico meaning "small quantity" 
femto   from Danish, or Norwegian word femten meaning "fifteen"
atto    from Danish, or Norwegian word atten meaning "eighteen"
The names zepto and zetta are derived from septo, from Latin septem which means seven (the seventh power of 10^3) and the letter 'z' is substituted for the letter 's' to avoid the duplicate use of the letter 's' as a symbol in SI. The names yocto and yotta are derived from Latin octo which means eight (the eighth power of 10^3); the letter 'y' is added to avoid the use of the letter 'o' as a symbol because it may be confused with the number zero. The CGPM has decided to name the prefixes, starting with the seventh power of 10^3, with the letters of the Latin alphabet, but starting from the end. Therefore the choice of letters 'z' and 'y'. The initial letter 'h' of the word hexa in standard French is silent, so it was removed in order to simplify things.
