Noun: femtometer
Usage: US (elsewhere: femtometre)
Usage: US (elsewhere: femtometre)
- A metric unit of length equal to one quadrillionth of a meter
"The size of an atomic nucleus is measured in femtometers";
- femtometre [Brit, Cdn], fermi
Derived forms: femtometers
Type of: metric linear unit
Part of: micromicron, picometer [US], picometre [Brit, Cdn]
Encyclopedia: Femtometer