English

femtoscale

From femto- + scale.

Proto-Germanic *fimftehun ‘fifteen’

Old Norse fimmtán ‘fifteen’

Danish femten ‘fifteen’

Proto-Indo-European *skend- ‘to jump up, ascend’

Proto-Indo-European *(s)kn̥d-sleh₂

Proto-Italic *skand-slā

Latin scāla ‘ladder; stairs’

Middle English scale ‘ladder’

English scale

Today it means

adj On a scale measured in femtometers.

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

Etymograph / femtoscale