thallium
/ˈθæliəm/
"thallium" is a 8-letter English headword indexed on PlainSpell.
The verdict
“thallium” is uncommon English (frequency #70,326 among 3,151 “T” headwords), classed as a noun. The kind of spelling people second-guess.
- #70,326
- frequency rank, English
- 3,151
- “T” headwords
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A metallic chemical element (symbol Tl) with atomic number 81: a gray post-transition metal that discolors when exposed to air.
Corpus desk
Index EN-thallium · thallium · English
thallium · rank #70,326 · 0 variants · 0 confusables
- FREQ-RARE #70,326
- LEN-LONG 8 letters
- VOW-3 3 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-MID 3,151
- PHOTO-FINISH Tertullian
Nearest frequency peer: Tertullian (-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 “thallium”
Sparse band: bars invert rank so rarer forms read shorter
- tangling
tangling
29,680 corpus weight
- telegraphic
telegraphic
29,677 corpus weight
- Tertullian
Tertullian
29,676 corpus weight
- thallium
thallium
29,675 corpus weight
- Tibbs
Tibbs
29,673 corpus weight
- Tillie
Tillie
29,671 corpus weight
What this shows Long-tail view: where “thallium” sits against similarly uncommon English ranks.
| Property | Value |
|---|---|
| Headword | thallium |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈθæliəm/ |
| Letters | 8 |
| Frequency rank | #70,326 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “thallium” in English
Rare enough to double-check
thallium is uncommon English at frequency #70,326 among 3,151 “T” headwords, classed as anoun, transcribed /ˈθæliəm/. Rarity is why readers land here mid-draft. 2 senses are on record.
The misspelling generator found no plausible variants for thallium, which points to an orthography that plays by predictable English rules. This entry stands alone in our confusable dataset, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.
Etymologically, the entry records: Coined based on Ancient Greek θαλλός (thallós, “green branch”) (after the color of the radiation spectra), + -ium. The correct English form is thallium, spelled T-H-A-L-L-I-U-M.
Definition
- 1A metallic chemical element (symbol Tl) with atomic number 81: a gray post-transition metal that discolors when exposed to air.
- 2A single atom of this element.
Recorded use
Wiktionary exampleThese source excerpts show how thallium appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
Environmental authorities in Lüeyang County, Shaanxi province, discovered excessive levels of thallium in two of the Jialing River’s upstream tributaries on Jan. 20, according to a statement Monday. The concentration of thallium that day was 170% higher than the standard for Qingni River, one of the upstream tributaries bordering Gansu province.
Etymology
Coined based on Ancient Greek θαλλός (thallós, “green branch”) (after the color of the radiation spectra), + -ium.
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 "thallium", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 8 letters (nearest by frequency rank).