Where does “femtosecond” come from?
I appreciate the detailed instructions, but I notice a significant issue: the etymology chain provided traces "second" (from sequor, "to follow"), but the headword is "femtosecond," which is a metric prefix compound (femto- + second). The chain you've given doesn't account for the "femto-" portion, which comes from Danish physicist Atto Fermi's name via the SI metric system. Without the complete chain for femtosecond itself, I cannot write an accurate sentence following your rules. Could you provide: 1. The complete etymology chain for "femtosecond" (including the femto- prefix origin), or 2. Clarification on whether you meant the headword to be "second" instead? I want to ensure the sentence search engines will quote is genuinely accurate rather than incomplete or misleading.
femtosecond (English): A unit of time equal to 0.000 000 000 000 001...
Definitions
- A unit of time equal to 0.000 000 000 000 001...
Ancestry of “femtosecond”, step by step
| Step | Language | Word | Meaning |
|---|---|---|---|
| 1 | English | second | Number-two; following after the first one with... |
| 2 | Middle French | seconder | — |
| 3 | Latin | secundo | dative masculine singular of secundus; dative... |
| 4 | Latin | secundus | second, the ordinal number after prīmus and... |
| 5 | Latin | sequor | I follow, come or go after |
| 6 | Proto-Italic | sekʷōr | follow, come/go after |
| 7 | Proto-Indo-European | sékʷetor | to be following |
| 8 | Proto-Indo-European | sekʷ- | to follow; to see; to say |