Which to use
“ad” is a noun and “af” is an adjective - they look or sound alike but fill different roles in a sentence.
- #5,365
- “ad” frequency rank
- #20,246
- “af” frequency rank
- 25611
- confusion score
Side-by-Side Comparison
| Feature | ad | af |
|---|---|---|
| Definition | Nombre. | Enfermo. |
Where the spellings diverge
Shared letters are muted; the letters that actually set ad and af apart are highlighted. They share 1 letter in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
ad and af form a confusable pair in the Spanish index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They differ by a single letter - d in “ad” becomes f in “af” - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 25611, derived from the frequency rank of both members and their visual similarity.
ad is recorded at frequency rank #5,365, classified as anoun, pronounced [ɑd]. af is at rank #20,246, tagged as anadj, pronounced /af/.
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 25611, this pair ranks #235,631 of 323,831 scored Spanish confusable pairs - roughly mid-pack for confusability.
Frequency comparison
Frequently Asked Questions
Can "ad" and "af" be used interchangeably?
Remembering ad vs af
The fastest way to pick the right one every time.
- Check the role first: if you need a noun, it's “ad”; for an adjective, it's “af”.
- See each word in full, definition, IPA, etymology and its other confusables. Full “ad” entry
- Browse more pairs most likely to be confused. Most confusable