Which to use
“ILS” and “ISR” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #39,360
- “ILS” frequency rank
- #49,434
- “ISR” frequency rank
- 88794
- confusion score
Side-by-Side Comparison
| Feature | ILS | ISR |
|---|---|---|
| Definition | Initialism of instrument landing system. | Initialism of interrupt service routine. |
Where the spellings diverge
Shared letters are muted; the letters that actually set ILS and ISR apart are highlighted. They share 2 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
ILS and ISR are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 88794, derived from the frequency rank of both members and their visual similarity.
ILS is recorded at frequency rank #39,360, classified as anoun. ISR is at rank #49,434, tagged as anoun.
Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.
With a confusion score of 88794, this pair ranks #5,901 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of ILS vs ISR
Shared letters: is. Private to "ILS": l. Private to "ISR": r.
"ILS" · 3 letters · shape VCC · "ISR" · 3 letters · shape VCC
Frequency comparison
Frequently Asked Questions
Can "ILS" and "ISR" be used interchangeably?
Which is more common, "ILS" or "ISR"?
Remembering ILS vs ISR
The fastest way to pick the right one every time.
- Read both glosses above and match the meaning you intend, only context separates this pair.
- See each word in full, definition, IPA, etymology and its other confusables. Full “ILS” entry
- Browse more pairs most likely to be confused. Most confusable