arbitrarilyvsarbitraryTell them apart

Quick tell: arbitrarily is a adverb, arbitrary is an adjective, so they fill different roles in a sentence.

Which to use

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

#21,722
“arbitrarily” frequency rank
#8,890
“arbitrary” frequency rank
30612
confusion score

Side-by-Side Comparison

Feature arbitrarily arbitrary
Definition In an arbitrary manner. Based on individual discretion or judgment; not based on any objective distinction, perhaps even made at random.

Letter map: arbitrarily vs arbitrary

Shared letters muted; letters that set arbitrarily and arbitrary apart highlighted. Shared run: 9.

11 ch
arbitrarily
9 ch
arbitrary

Part-of-speech tell for arbitrarily / arbitrary

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: arbitrarily is anadverb and arbitraryanadjective. On the page they differ by 2 letter(s) in length. Our composite confusion score for this pair is 30612, derived from the frequency rank of both members and their visual similarity.

arbitrarily is recorded at frequency rank #21,722, classified as anadv. arbitrary is at rank #8,890, tagged as anadj, pronounced /ˈɑː.bɪ.tɹə.ɹi/.

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 30612, this pair ranks #353,123 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of arbitrarily vs arbitrary

Shared letters: abirty. Private to "arbitrarily": l. Private to "arbitrary": -.

"arbitrarily" · 11 letters · shape VCCVCCVCVCV  ·  "arbitrary" · 9 letters · shape VCCVCCVCV

Known mistypes of this pair

  • arbitrarilyabritrarily · arbbitrarily · arbirtarily · arbitarrily · arbitrairly · arbitrarilly · arbitrarilyy · arbitrariyl
  • arbitraryabritrary · arbbitrary · arbirtary · arbitarry · arbitrarry · arbitraryy · arbitrayr · arbitrrary

Frequently Asked Questions

Is swapping "arbitrarily" for "arbitrary" ever safe?
No - they are not even the same part of speech. "arbitrarily" is an adverb and "arbitrary" an adjective, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "arbitrarily" vs "arbitrary" - which ranks higher?
"arbitrary" is the more common of the two: it sits at frequency rank #8,890 in our English list, against #21,722 for "arbitrarily". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Pair "arbitrarily" vs "arbitrary" is on the table, pick a follow-up below.

  • Full dictionary entry for "arbitrarily" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "arbitrary" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #353,123 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "arbitrarily" and "arbitrary" also get mixed up with nearby pairs, the highest-scored neighbour is "arbitrage vs arbitrary". 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 #353,123 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list