scumvssumConfusable pair

Which to use

“scum” and “sum” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#11,112
“scum” frequency rank
#4,050
“sum” frequency rank
15162
confusion score

Side-by-Side Comparison

Feature scum sum
Definition A layer of impurities that accumulates at the surface of a liquid (especially molten metal or water). A quantity obtained by addition or aggregation.

Where the eye mixes scum and sum

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
scum
3 ch
sum

Visual trap between scum and sum

A purely visual mix-up. scum (/skʌm/) and sum (/sʌm/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 15162, derived from the frequency rank of both members and their visual similarity.

scum is recorded at frequency rank #11,112, classified as anoun, pronounced /skʌm/. sum is at rank #4,050, tagged as anoun, pronounced /sʌm/.

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 15162, this pair ranks #465,697 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of scum vs sum

Shared letters: msu. Private to "scum": c. Private to "sum": -.

"scum" · 4 letters · shape CCVC  ·  "sum" · 3 letters · shape CVC

Known mistypes of this pair

  • scumcsum · sccum · scmu · scumm · sscum · sucm

Frequently Asked Questions

Is swapping "scum" for "sum" ever safe?
No. They are said differently (/skʌm/ versus /sʌm/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "scum" vs "sum" - which ranks higher?
"sum" is the more common of the two: it sits at frequency rank #4,050 in our English list, against #11,112 for "scum". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "scum" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sum" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #465,697 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "scum" and "sum" also get mixed up with nearby pairs, the highest-scored neighbour is "SCSI vs scum". 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 #465,697 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