actvsanWhat's the difference?

Quick tell: act is a verb, an is an adverb, so they fill different roles in a sentence.

Which to use

“act” is a verb and “an” is an adverb - they look or sound alike but fill different roles in a sentence.

#9,948
“act” frequency rank
#2,817
“an” frequency rank
12765
confusion score

Side-by-Side Comparison

Feature act an
Definition agir ligado, aceso:

Letter map: act vs an

Shared letters muted; letters that set act and an apart highlighted. Shared run: 1.

3 ch
act
2 ch
an

Role in the sentence - act and an

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: act is averb and ananadverb. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 12765, derived from the frequency rank of both members and their visual similarity.

act is recorded at frequency rank #9,948, classified as averb. an is at rank #2,817, tagged as anadv, pronounced /an/.

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 12765, this pair ranks #59,723 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of act vs an

Shared letters: a. Private to "act": ct. Private to "an": n.

"act" · 3 letters · shape VCC  ·  "an" · 2 letters · shape VC

Frequently Asked Questions

Can "act" and "an" be used interchangeably?
No - they are not even the same part of speech. "act" is a verb and "an" an adverb, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "act" or "an"?
"an" is the more common of the two: it sits at frequency rank #2,817 in our Portuguese list, against #9,948 for "act". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Done with this confusable. These links stay specific to "act" and "an".

  • Full dictionary entry for "act" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "an" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #59,723 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "act" and "an" also get mixed up with nearby pairs, the highest-scored neighbour is "acs vs act". Nearby pair

Confusion rank #59,723 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list