Which to use
“ache” is a noun and “acid” is an adjective - they look or sound alike but fill different roles in a sentence.
- #9,947
- “ache” frequency rank
- #44,664
- “acid” frequency rank
- 54611
- confusion score
Side-by-Side Comparison
| Feature | ache | acid |
|---|---|---|
| Definition | dor, axe | ácido, que possui acidez; |
Letter map: ache vs acid
Shared letters muted; letters that set ache and acid apart highlighted. Shared run: 2. ache (VCCV) and acid (VCVC) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.
Part-of-speech tell for ache / acid
Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: ache is anoun and acidanadjective. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 54611, derived from the frequency rank of both members and their visual similarity.
ache is recorded at frequency rank #9,947, classified as anoun, pronounced /eɪk/. acid is at rank #44,664, tagged as anadj.
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 54611, this pair ranks #11,143 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.
Orthographic DNA of ache vs acid
Shared letters: ac. Private to "ache": eh. Private to "acid": di.
"ache" · 4 letters · shape VCCV · "acid" · 4 letters · shape VCVC
Known mistypes of this pair
Frequently Asked Questions
Is swapping "ache" for "acid" ever safe?
Frequency check: "ache" vs "acid" - which ranks higher?
Useful next steps
Done with this confusable. These links stay specific to "ache" and "acid".
- Full dictionary entry for "ache" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "acid" - compare definitions side by side with the headword page. Word entry
- This pair ranks #11,143 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
- "ache" and "acid" also get mixed up with nearby pairs, the highest-scored neighbour is "acid vs acs". Nearby pair
- Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes
Confusion rank #11,143 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.