ISS
"iss" is a 3-letter English headword indexed on PlainSpell.
The verdict
“ISS” sits in 20 confusable pairs (corpus #16,055) as a proper noun. The look-alike neighbours are the real trap.
- #16,055
- frequency rank, English
- 2,140
- “I” headwords
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of International Space Station.
Corpus desk
Index EN-iss · ISS · English
ISS · rank #16,055 · 0 variants · 20 confusables
- FREQ-MID #16,055
- LEN-MID 3 letters
- VOW-1 1 vowel
- CONFUS-HIGH 20 pairs
- VAR-0 0 variants
- BOOK-MID 2,140
- PHOTO-FINISH jars
Nearest frequency peer: jars (+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.
Frequency neighbours of confusable “ISS”
Peers at similar corpus weight, separate from look-alike pairs below
- insensitive
insensitive
83,949 corpus weight
- interpreting
interpreting
83,948 corpus weight
- ISS
ISS
83,946 corpus weight
- jars
jars
83,945 corpus weight
- keystone
keystone
83,944 corpus weight
- knitting
knitting
83,943 corpus weight
What this shows Bars place “ISS” against nearest ranked English headwords, not a reprint of the confusable-pair desk.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | ISS |
| Language | English |
| Part of speech | Proper noun |
| Letters | 3 |
| Frequency rank | #16,055 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Corpus rank beside confusables of “ISS”
Easy to mix with look-alikes
The spelling risk for ISS is neighbouring look-alikes ("it", "IV", …), not just typos; it is aproper noun. Frequency #16,055 among 2,140 “I” headwords. Gloss: "Initialism of International Space Station.".
ISS has no tracked misspelling variants, suggesting the orthography follows predictable English patterns. It also participates in 20 confusable-pair relationships, "it", "IV", "iz", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.
This entry's etymology isn't recorded, so its spelling is best read as a straightforward mapping from sound to letter. The correct English form is ISS, spelled I-S-S.
Definition
- 1Initialism of International Space Station.
Recorded use
Wiktionary exampleThese source excerpts show how ISS appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
Before Musk, America’s space industry was moribund. In 2011, NASA mothballed the last space shuttle, after inking a deal with SpaceX to make uncrewed cargo resupply runs to the International Space Station (ISS). […] SpaceX launched its first crew to the ISS aboard a Dragon spacecraft in May 2020.
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 "ISS", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 3 letters (nearest by frequency rank).