unclevsundueWhat's the difference?

Quick tell: uncle is a noun, undue is an adjective, so they fill different roles in a sentence.

Which to use

“uncle” is a noun and “undue” is an adjective - they look or sound alike but fill different roles in a sentence.

#3,342
“uncle” frequency rank
#20,003
“undue” frequency rank
23345
confusion score

Side-by-Side Comparison

Feature uncle undue
Definition The brother or brother-in-law of one’s parent. Excessive; going beyond that what is natural or sufficient.

Where the spellings diverge

Shared letters are muted; the letters that actually set uncle and undue apart are highlighted. They share 3 letters in sequence, which is exactly why the eye skips the difference.

5 ch
uncle
5 ch
undue

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: uncle is /ˈʌŋ.kl̩/ while undue is /ʌnˈdjuː/. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (noun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 23345, derived from the frequency rank of both members and their visual similarity.

uncle is recorded at frequency rank #3,342, classified as anoun, pronounced /ˈʌŋ.kl̩/. undue is at rank #20,003, tagged as anadj, pronounced /ʌnˈdjuː/.

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 23345, this pair ranks #409,989 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of uncle vs undue

Shared letters: enu. Private to "uncle": cl. Private to "undue": d.

"uncle" · 5 letters · shape VCCCV  ·  "undue" · 5 letters · shape VCCVV

Known mistypes of this pair

  • unclenucle · ucnle · unccle · uncel · unclle · unlce · unncle
  • unduenudue · udnue · unddue · undeu · unndue · unude

Frequency comparison

uncle#3,342
undue#20,003

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "uncle" and "undue" be used interchangeably?
No - they are not even the same part of speech. "uncle" is a noun and "undue" an adjective, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "uncle" or "undue"?
"uncle" is the more common of the two: it sits at frequency rank #3,342 in our English list, against #20,003 for "undue". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering uncle vs undue

The fastest way to pick the right one every time.

  • Check the role first: if you need a noun, it's “uncle”; for an adjective, it's “undue”.
  • See each word in full, definition, IPA, etymology and its other confusables. Full “uncle” 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