Etymograph

English

femtobel

From femto- + bel.

A compound of femto- + bel

Proto-Germanic *fimftehun ‘fifteen’

Old Norse fimmtán ‘fifteen’

Danish femten ‘fifteen’

English femto-

Today it means

noun An SI unit of relative power equal to 10⁻¹⁵ bels. Symbol: f

Language periods are conventional ranges, not dates for this word.

Etymograph / femtobel