SifvssudWhich spelling fits?

Quick tell: Sif is a name, sud is a noun, so they fill different roles in a sentence.

Which to use

“Sif” is a name and “sud” is a noun - they look or sound alike but fill different roles in a sentence.

#49,636
“Sif” frequency rank
#37,717
“sud” frequency rank
87353
confusion score

Side-by-Side Comparison

Feature Sif sud
Definition A golden-haired goddess associated with earth, mother of Ullr and wife of Thor. A bubble of lather or foam (the singular of suds).

Where the eye mixes Sif and sud

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence. Sif and sud follow the identical consonant-vowel pattern (CVC). Same shape at a glance is often the real trap, independent of shared letters.

3 ch
Sif
3 ch
sud

Why the eye confuses Sif with sud

These two trip readers on the page rather than in the ear: Sif is /sɪf/ while sud is /sʌd/. 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 (name vs noun), which is usually the fastest check. Our composite confusion score for this pair is 87353, derived from the frequency rank of both members and their visual similarity.

Sif is recorded at frequency rank #49,636, classified as aname, pronounced /sɪf/. sud is at rank #37,717, tagged as anoun, pronounced /sʌd/.

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 87353, this pair ranks #7,720 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of Sif vs sud

Shared letters: s. Private to "Sif": fi. Private to "sud": du.

"Sif" · 3 letters · shape CVC  ·  "sud" · 3 letters · shape CVC

Frequently Asked Questions

Is swapping "Sif" for "sud" ever safe?
No - they are not even the same part of speech. "Sif" is a name and "sud" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "Sif" vs "sud" - which ranks higher?
"sud" is the more common of the two: it sits at frequency rank #37,717 in our English list, against #49,636 for "Sif". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Eye-level mix-up between "Sif" and "sud" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "Sif" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sud" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #7,720 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "Sif" and "sud" also get mixed up with nearby pairs, the highest-scored neighbour is "SDP vs Sif". Nearby pair

Confusion rank #7,720 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