femto-
[ˈfẽmt̪o]
The verdict
“femto-” is uncommon Spanish (outside the top frequency list), classed as a prefix. The kind of spelling people second-guess.
- Unranked
- below top-frequency Spanish
- 6
- letters
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Prefijo del Sistema Internacional utilizado para denotar la milbillonésima parte de la unidad o, equivalentemente, la multiplicación por un factor de 10⁻¹⁵. Su símbolo es f.
Corpus desk
Index ES-femto · femto- · Spanish
femto- · unranked · 0 variants · 0 confusables
- FREQ-UNRANKED Unranked
- LEN-LONG 6 letters
- VOW-2 2 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-THIN "F" thin
- PHOTO-UNK Peer pending
Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.
| Property | Value |
|---|---|
| Headword | femto- |
| Language | Spanish |
| Part of speech | Prefix |
| IPA | [ˈfẽmt̪o] |
| Letters | 6 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Cola larga: rango de “femto-” en español
Rare enough to double-check
femto- is uncommon Spanish outside the top frequency list, classed as aprefix, transcribed [ˈfẽmt̪o]. Rarity is why readers land here mid-draft. Gloss: "Prefijo del Sistema Internacional utilizado para denotar la milbillonésima parte de la unidad o, equivalentemente, la multiplicación por un factor de 10⁻¹⁵. Su símbolo es f.".
We couldn't generate a plausible misspelling set for femto-, which points to an orthography that plays by predictable Spanish rules. Our dataset records no confusable match here, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.
No explicit etymology string is stored for this entry, so any spelling logic here comes from how the word's sounds map to letters, not a documented origin story. The correct Spanish form is femto-, spelled F-E-M-T-O--.
Definition
- 1Prefijo del Sistema Internacional utilizado para denotar la milbillonésima parte de la unidad o, equivalentemente, la multiplicación por un factor de 10⁻¹⁵. Su símbolo es f.
Recorded use
Wiktionary exampleThese source excerpts show how femto- appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
un protón tiene un diámetro aproximado de 1.6 femtómetros.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.