fortiesvsfortressWhat's the difference?

Which to use

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

#27,467
“forties” frequency rank
#10,051
“fortress” frequency rank
37518
confusion score

Side-by-Side Comparison

Feature forties fortress
Definition The fifth decade of a century: the 1840s, 1940s, 2040s, etc. A fortified place; a large and permanent fortification, sometimes including a town; for example a fort, a castle; a stronghold; a place of defense or security.

Letter map: forties vs fortress

Shared letters muted; letters that set forties and fortress apart highlighted. Shared run: 6. forties runs 7 letters (CVCCVVC) against fortress's 8 (CVCCCVCC) - the length gap alone is often enough to separate them once you know to check it.

7 ch
forties
8 ch
fortress

Spelling & dictionary notes on forties vs fortress

forties and fortress are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 37518, derived from the frequency rank of both members and their visual similarity.

forties is recorded at frequency rank #27,467, classified as anoun. fortress is at rank #10,051, tagged as anoun, pronounced /ˈfoɹ.tɹɪs/.

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 37518, this pair ranks #293,880 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of forties vs fortress

Shared letters: eforst. Private to "forties": i. Private to "fortress": -.

"forties" · 7 letters · shape CVCCVVC  ·  "fortress" · 8 letters · shape CVCCCVCC

Known mistypes of this pair

  • forties ← fforties · forites · forrties · forteis · fortiess · fortise · fortties · fotries
  • fortress ← ffortress · forrtess · forrtress · forterss · fortres · fortrress · fortrses · forttress

Frequently Asked Questions

Can "forties" and "fortress" be used interchangeably?
No. They differ by 1 letter(s) in length, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Frequency check: "forties" vs "fortress" - which ranks higher?
"fortress" is the more common of the two: it sits at frequency rank #10,051 in our English list, against #27,467 for "forties". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Done with this confusable. These links stay specific to "forties" and "fortress".

  • Full dictionary entry for "forties" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "fortress" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #293,880 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "forties" and "fortress" also get mixed up with nearby pairs, the highest-scored neighbour is "forties vs fortify". 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 #293,880 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