femto-

1. a combining form used in the names of units of measurement which are 10− 15 (one quadrillionth) smaller than the unit denoted by the base word.

femto-

prefix

1. f. denoting 10 ^–15

   femtometer

Word History and Origins

Origin of femto-¹

< Danish, Norwegian femt ( en ) fifteen + -o-

Word History and Origins

Origin of femto-¹

from Danish or Norwegian femten fifteen

Example Sentences

Griffith dies and is reborn as Femto, a member of the God Hand, who is undeterred by moral inhibitions.

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Femto becomes the spearhead of the God Hand’s schemes.

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Far to the right side of the decimal point—beyond milli, micro, nano, pico, and femto—lives the atto, the metric prefix representing 10-18.

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His pioneering work came in an area known by the exotic sounding name of femtochemistry, where femto is a prefix used to suggest quantities and time intervals on the order of a millionth of a billionth of those encountered in the everyday world.

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Just as slow-motion photography revealed aspects of common events hidden from the scrutiny of the unaided human senses, “femto” techniques, embodying laser capabilities, gave science new insights into how chemical reactions proceed.

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