SINCE 1828

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femtometer

noun fem·to·me·ter \ ˈfem(p)-tə-ˌmē-tər , -tō- \

Definition of femtometer

: a unit of length equal to 10⁻¹⁵ meters : one quadrillionth of a meter

Origin and Etymology of femtometer

femto- + ³meter

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First Known Use: 1971

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