flatline
/ˈflætˌlaɪn/
"flatline" is a 8-letter English headword indexed on PlainSpell.
The verdict
“flatline” is uncommon English (frequency #62,898 among 2,507 “F” headwords), classed as a noun. The kind of spelling people second-guess.
- #62,898
- frequency rank, English
- 2,507
- “F” headwords
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - An asystole; the absence of heart contractions or brain waves.
Corpus desk
Index EN-flatline · flatline · English
flatline · rank #62,898 · 0 variants · 0 confusables
- FREQ-RARE #62,898
- LEN-LONG 8 letters
- VOW-3 3 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-MID 2,507
- PHOTO-FINISH fisheye
Nearest frequency peer: fisheye (-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 “flatline”
Sparse band: bars invert rank so rarer forms read shorter
- Fiedler
Fiedler
37,106 corpus weight
- fisheye
fisheye
37,104 corpus weight
- flatline
flatline
37,103 corpus weight
- Flaubert
Flaubert
37,102 corpus weight
- flitting
flitting
37,101 corpus weight
- flycatcher
flycatcher
37,100 corpus weight
What this shows Long-tail view: where “flatline” sits against similarly uncommon English ranks.
| Property | Value |
|---|---|
| Headword | flatline |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈflætˌlaɪn/ |
| Letters | 8 |
| Frequency rank | #62,898 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “flatline” in English
Rare enough to double-check
flatline is uncommon English at frequency #62,898 among 2,507 “F” headwords, classed as anoun, transcribed /ˈflætˌlaɪn/. Rarity is why readers land here mid-draft. 4 senses are on record.
The misspelling generator found no plausible variants for flatline, since its letter pattern doesn't lend itself to common typo substitutions. This entry stands alone in our confusable dataset, which typically means the spelling is too distinctive to be mistaken for another word.
Etymologically, the entry records: From flat + line. Refers to a continuous straight line (asystole) on an ECG (EKG) or EEG, indicating death. The correct English form is flatline, spelled F-L-A-T-L-I-N-E.
Definition
- 1An asystole; the absence of heart contractions or brain waves.
- 2An asystole; the absence of heart contractions or brain waves.
- 3An unchanging state, as indicated in a graph of a variable over time.
- 4A line that is run low to the water from the rod tip, generally off a release clip of some type.
Recorded use
Wiktionary examplesThese source excerpts show how flatline appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
When brain function ceases, the electroencephalogram shows flatline recordings.
Thus, you hear words like "flatline recession," "improvement at a greatly reduced rate," "economic hiccup," "recessionette," "rolling readjustment" and "the economy is double clutching."
Etymology
From flat + line. Refers to a continuous straight line (asystole) on an ECG (EKG) or EEG, indicating death.
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 "flatline", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 8 letters (nearest by frequency rank).