irregularvsirregularlyWhat's the difference?

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

Which to use

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

#11,238
“irregular” frequency rank
#34,548
“irregularly” frequency rank
45786
confusion score

Side-by-Side Comparison

Feature irregular irregularly
Definition Nonstandard; not conforming to rules or expectations. In an irregular manner; without rule, method, or order.

Where the spellings diverge

Shared letters are muted; the letters that actually set irregular and irregularly apart are highlighted. They share 9 letters in sequence, which is exactly why the eye skips the difference.

9 ch
irregular
11 ch
irregularly

Spelling & Dictionary Insight

irregular and irregularly form a confusable pair in the English index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They differ by 2 extra letter(s) - “irregular” sits inside “irregularly” - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 45786, derived from the frequency rank of both members and their visual similarity.

irregular is recorded at frequency rank #11,238, classified as anadj, pronounced /ɪˈɹɛɡ.jʊ.lə/. irregularly is at rank #34,548, tagged as anadv, pronounced /ɪˈɹɛɡjʊləli/.

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 45786, this pair ranks #217,922 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Frequency comparison

irregular#11,238
irregularly#34,548

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "irregular" and "irregularly" be used interchangeably?
No, "irregular" and "irregularly" have distinct meanings and cannot be swapped without changing the meaning of a sentence. Understanding the specific definition and context for each word is essential for correct usage.

Remembering irregular vs irregularly

The fastest way to pick the right one every time.

  • Check the role first: if you need an adjective, it's “irregular”; for an adverb, it's “irregularly”.
  • See each word in full, definition, IPA, etymology and its other confusables. Full “irregular” entry
  • Browse more pairs most likely to be confused. Most confusable

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

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list