tachyon
/ˈtæk.i.ɒn/
"tachyon" is a 7-letter English headword indexed on PlainSpell.
The verdict
“tachyon” is uncommon English (frequency #74,558 among 3,151 “T” headwords), classed as a noun. The kind of spelling people second-guess.
- #74,558
- frequency rank, English
- 3,151
- “T” headwords
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A hypothetical particle that travels faster than the speed of light.
Corpus desk
Index EN-tachyon · tachyon · English
tachyon · rank #74,558 · 0 variants · 0 confusables
- FREQ-RARE #74,558
- LEN-LONG 7 letters
- VOW-3 3 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-MID 3,151
- PHOTO-FINISH tachometer
Nearest frequency peer: tachometer (-1 rank slots)
Read with this headword: Spelling guide for this pattern
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.
Long-tail ranks near “tachyon”
Sparse band: bars invert rank so rarer forms read shorter
- swee
swee
25,446 corpus weight
- symbology
symbology
25,445 corpus weight
- tachometer
tachometer
25,444 corpus weight
- tachyon
tachyon
25,443 corpus weight
- tamas
tamas
25,441 corpus weight
- taproom
taproom
25,440 corpus weight
What this shows Long-tail view: where “tachyon” sits against similarly uncommon English ranks.
| Property | Value |
|---|---|
| Headword | tachyon |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈtæk.i.ɒn/ |
| Letters | 7 |
| Frequency rank | #74,558 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “tachyon” in English
Rare enough to double-check
tachyon is uncommon English at frequency #74,558 among 3,151 “T” headwords, classed as anoun, transcribed /ˈtæk.i.ɒn/. Rarity is why readers land here mid-draft. 2 senses are on record.
tachyon has no tracked misspelling variants, since its letter sequence doesn't invite the usual edit-distance slips. It is not paired with a close-neighbour confusable in our dataset, which tends to mean the word is visually distinctive enough to stand on its own.
Etymologically, the entry records: Formed as: tachy- + -on, from ταχύς (takhús, “swift”, “rapid”). Coined by American physicist Gerald Feinberg in 1967. The correct English form is tachyon, spelled T-A-C-H-Y-O-N.
Definition
- 1A hypothetical particle that travels faster than the speed of light.
- 2A flaw in a physical theory that predicts the existence of tachyons or similar paradoxical results. Compare with ghost.
Etymology
Formed as: tachy- + -on, from ταχύς (takhús, “swift”, “rapid”). Coined by American physicist Gerald Feinberg in 1967.
Synonyms
This word in other languages
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
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Similar English words by spelling shape
Same letter count and similar misspelling depth for "tachyon", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 7 letters (nearest by frequency rank).