FEIvsfoxWhat's the difference?

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

Which to use

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

#22,967
“FEI” frequency rank
#2,204
“fox” frequency rank
25171
confusion score

Side-by-Side Comparison

Feature FEI fox
Definition Initialism of Federal Executive Institute. A small-to-medium-sized canine mammal, related to dogs and wolves, with a flattened skull, upright triangular ears, a pointed, slightly upturned snout, and a long bushy tail, of the following groups:

Letter map: FEI vs fox

Shared letters muted; letters that set FEI and fox apart highlighted. Shared run: 1.

3 ch
FEI
3 ch
fox

Grammar separator: FEI vs fox

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: FEI is aname and foxanoun. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 25171, derived from the frequency rank of both members and their visual similarity.

FEI is recorded at frequency rank #22,967, classified as aname. fox is at rank #2,204, tagged as anoun, pronounced /fɒks/.

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 25171, this pair ranks #396,370 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of FEI vs fox

Shared letters: f. Private to "FEI": ei. Private to "fox": ox.

"FEI" · 3 letters · shape CVV  ·  "fox" · 3 letters · shape CVC

Frequently Asked Questions

Can "FEI" and "fox" be used interchangeably?
No - they are not even the same part of speech. "FEI" is a name and "fox" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "FEI" or "fox" show up more?
"fox" is the more common of the two: it sits at frequency rank #2,204 in our English list, against #22,967 for "FEI". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Useful next steps

Pair "FEI" vs "fox" is on the table, pick a follow-up below.

  • Full dictionary entry for "FEI" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "fox" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #396,370 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "FEI" and "fox" also get mixed up with nearby pairs, the highest-scored neighbour is "FEI vs foh". Nearby pair

Confusion rank #396,370 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