unobservable
"unobservable" is a 12-letter English headword indexed on PlainSpell.
The verdict
“unobservable” is uncommon English (frequency #96,618 among 1,433 “U” headwords), classed as an adjective. The kind of spelling people second-guess.
- #96,618
- frequency rank, English
- 1,433
- “U” headwords
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - That cannot be observed.
Corpus desk
Index EN-unobservable · unobservable · English
unobservable · rank #96,618 · 0 variants · 0 confusables
- FREQ-RARE #96,618
- LEN-MEGA 12 letters
- VOW-5 5 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-MID 1,433
- PHOTO-FINISH unselfishly
Nearest frequency peer: unselfishly (+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 “unobservable”
Sparse band: bars invert rank so rarer forms read shorter
- ungraded
ungraded
3,387 corpus weight
- unkindly
unkindly
3,385 corpus weight
- unobservable
unobservable
3,383 corpus weight
- unselfishly
unselfishly
3,382 corpus weight
- unsexy
unsexy
3,381 corpus weight
- unsheathed
unsheathed
3,380 corpus weight
What this shows Long-tail view: where “unobservable” sits against similarly uncommon English ranks.
| Property | Value |
|---|---|
| Headword | unobservable |
| Language | English |
| Part of speech | Adjective |
| Letters | 12 |
| Frequency rank | #96,618 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “unobservable” in English
Rare enough to double-check
unobservable is uncommon English at frequency #96,618 among 1,433 “U” headwords, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "That cannot be observed.".
The misspelling generator found no plausible variants for unobservable, and the word's spelling is regular enough that our generator found nothing worth flagging. No close-neighbour confusable shows up for this headword in our dataset, since its spelling is unusual enough that it doesn't cluster with a lookalike.
Etymologically, the entry records: From un- + observable. The correct English form is unobservable, spelled U-N-O-B-S-E-R-V-A-B-L-E.
Definition
- 1That cannot be observed.
Etymology
From un- + observable.
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 "unobservable", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 12 letters (nearest by frequency rank).