Usage examples (6)

• I'm sure that there's a reason you started to ask about making some kind of measurement at the 100 femtometer level but for now you've just baffled me.
• Femto-neutrons or 'femtons' are fast neutrons of femtometer wavelength, a million times shorter than the current nanotechnology diagnostic probes which operate on...
• The first unit to go into the field, pictured below, "can detect a 10 femtometer change in the position of its center chip.
• 0.8768 femtometers, (a femtometer equals one quadrillionth of a meter).