fortress

/ˈfoɹ.tɹɪs/

//ˈfoɹ.tɹɪs// noun

"fortress" is a 8-letter English headword indexed on PlainSpell.

The verdict

“fortress” is a moderately-common English word, ranked #10,051 in English word frequency and used as a noun.

#10,051
frequency rank, English
8
letters
11
tracked misspellings
2
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - 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.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

fortress vs Forrest
63% similar
fortress vs forties
75% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for fortress
PropertyValue
Headwordfortress
LanguageEnglish
Part of speechNoun
IPA/ˈfoɹ.tɹɪs/
Letters8
Frequency rank#10,051
Misspellings tracked11
Confusable pairs2
SourceWiktionary (kaikki.org)

Where “fortress” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). fortress lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for fortress is 8 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈfoɹ.tɹɪs/. Corpus data places it at rank #10,051 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 11 likely wrong-spelling variants for fortress, with forms such as "ffortress", "forrtess", and "forrtress". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 2 confusable-pair relationships, "Forrest", "forties", since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: Early 14 c., from Old French forteresce, forteresse, forterece (“strong place, fortification”), variant of fortelesse, from Medieval Latin fortalitia, from Latin fortis (“strong”) (see fort) + -itia, added to adjectives to form nouns of quality or condition… The correct English form is fortress, spelled F-O-R-T-R-E-S-S.

Definition

  1. 1
    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.
  2. 2
    A position that, if obtained by the weaker side, will prevent penetration by the opposing side, generally achieving a draw.

Etymology

Early 14 c., from Old French forteresce, forteresse, forterece (“strong place, fortification”), variant of fortelesse, from Medieval Latin fortalitia, from Latin fortis (“strong”) (see fort) + -itia, added to adjectives to form nouns of quality or condition. French -ess, from Latin -itia is also in words such as duress, prowess, largesse and richesse. For change of medial -l- to -r- in Old French, compare orne (“elm”) from ulmus; chartre from cartula and chapitre from capitulum. First attested in the 12th century.

Synonyms

This word in other languages

Common misspellings

Also misspelled as: ffortress,forrtess,forrtress,forterss,fortres,fortrress,fortrses,forttress,fotrress,frotress,ofrtress

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of fortress - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

ffortress1forrtess2forrtress1forterss2fortres1fortrress1fortrses2forttress1
Edit distance from "fortress"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "fortress"?
"fortress" is spelled F-O-R-T-R-E-S-S. The IPA pronunciation is /ˈfoɹ.tɹɪs/.
What does "fortress" mean?
As a noun, "fortress" means: 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.
What words are commonly confused with "fortress"?
"fortress" is commonly confused with "Forrest", "forties". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "fortress"?
The IPA (International Phonetic Alphabet) transcription for "fortress" is /ˈfoɹ.tɹɪs/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "fortress"?
Early 14 c., from Old French forteresce, forteresse, forterece (“strong place, fortification”), variant of fortelesse, from Medieval Latin fortalitia, from Latin fortis (“strong”) (see fort) + -itia, added to adjectives to form nouns of quality or... See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “fortress”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is F-O-R-T-R-E-S-S - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈfoɹ.tɹɪs/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “Forrest” - see the side-by-side comparison. fortress vs Forrest
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list