strengthen

/ˈstɹɛŋ(k)θən/

//ˈstɹɛŋ(k)θən// verb

By · According to Wiktionary data (CC BY-SA) ·

"strengthen" is a 10-letter English headword indexed on PlainSpell.

The verdict

“strengthen” has 17 generated spelling variants in the English index at frequency #6,743. The variants make it a useful spelling check.

#6,743
frequency rank, English
6,566
“S” headwords
17
tracked misspellings
3
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - To make strong or stronger; to add strength to; to increase the strength of; to fortify.

Corpus desk

Index EN-strengthen · strengthen · English

strengthen · rank #6,743 · 17 variants · 3 confusables

  • FREQ-COMMON #6,743
  • LEN-MEGA 10 letters
  • VOW-2 2 vowels
  • CONFUS-LOW 3 pairs
  • VAR-HIGH 17 variants
  • BOOK-DENSE 6,566
  • PHOTO-FINISH sponsor

Nearest frequency peer: sponsor (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Rank peers near misspelling magnet “strengthen”

Same rarity band: useful when a typo lands on a peer headword

corpus weight

What this shows “strengthen” sits among these FrequencyWords peers; misspelling depth is tracked separately in the edit-distance chart.

Source FrequencyWords open word-frequency list As of September 3, 2026

Visual similarity to commonly confused words

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

strengthen vs strengths
80% similar
strengthen vs strengthened
83% similar
strengthen vs strength
80% similar

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

Key facts for strengthen
PropertyValue
Headwordstrengthen
LanguageEnglish
Part of speechVerb
IPA/ˈstɹɛŋ(k)θən/
Letters10
Frequency rank#6,743
Misspellings tracked17
Confusable pairs3
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “strengthen”

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).strengthenlands here:

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

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Same rarity band neighbours include “sponsor” (#6,742), “strings” (#6,744), “spite” (#6,741). Among 6,566 “S” headwords, “strengthen” is #6,743. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 17 spelling variants around strengthen (IPA /ˈstɹɛŋ(k)θən/), averb. Corpus frequency is #6,743 among 6,566 “S” headwords. Wiktionary lists 6 senses, so context still picks the gloss.

Our generated misspelling index lists 17 likely wrong-spelling variants for strengthen, with forms such as "srtengthen", "sstrengthen", and "sterngthen". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 3 confusable-pair relationships, "strengths", "strengthened", "strength", since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: From rare Middle English strengthenen (14th c.), from earlier strengthen (12th c.), where -en is the infinitive ending. Probably the original form was reinterpreted as strength + -en around the time when the infinitive ending was being apocopated in late Mi… The correct English form is strengthen, spelled S-T-R-E-N-G-T-H-E-N.

Definition

  1. 1
    To make strong or stronger; to add strength to; to increase the strength of; to fortify.
  2. 2
    To empower; to give moral strength to; to encourage; to enhearten.
  3. 3
    To augment; to improve; to intensify.
  4. 4
    To reinforce, to add to, to support (someone or something)
  5. 5
    To substantiate; to corroborate (a belief, argument, etc.)
  6. 6
    To grow strong or stronger.

Recorded use

Wiktionary examples

These source excerpts show how strengthen appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. strengthen a muscle
  2. strengthen a wall

Etymology

From rare Middle English strengthenen (14th c.), from earlier strengthen (12th c.), where -en is the infinitive ending. Probably the original form was reinterpreted as strength + -en around the time when the infinitive ending was being apocopated in late Middle English.

Synonyms

annealbracebuild upconfirmenstrengthenfortifyhardenintendindurateinvigoratemunitenervenerve upreinforceroboratesteelstrengthstrengthenthicken

Antonyms

weakenatrophydebilitateenervateenfeeble

This word in other languages

fortalecer(Español)renforcer(Français)verstärken(Deutsch)fortalecer(Português)

Common misspellings

Also misspelled as:

  • srtengthen
  • sstrengthen
  • sterngthen
  • stregnthen
  • strenggthen
  • strenghten
  • strengtehn
  • strengthenn
  • strengthhen
  • strengthne
  • strengtthen
  • strenngthen
  • strentghen
  • strnegthen
  • strrengthen
  • sttrengthen
  • tsrengthen

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of strengthen - 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.

srtengthen2sstrengthen1sterngthen2stregnthen2strenggthen1strenghten2strengtehn2strengthenn1
Edit distance from "strengthen"

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 "strengthen"?
"strengthen" is spelled S-T-R-E-N-G-T-H-E-N. The IPA pronunciation is /ˈstɹɛŋ(k)θən/.
What does "strengthen" mean?
As a verb, "strengthen" means: To make strong or stronger; to add strength to; to increase the strength of; to fortify.
What words are commonly confused with "strengthen"?
"strengthen" is commonly confused with "strengths", "strengthened", "strength". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "strengthen"?
The IPA (International Phonetic Alphabet) transcription for "strengthen" is /ˈstɹɛŋ(k)θən/. 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 "strengthen"?
From rare Middle English strengthenen (14th c.), from earlier strengthen (12th c.), where -en is the infinitive ending. Probably the original form was reinterpreted as strength + -en around the time when the infinitive ending was being apocopated ... 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.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "strengthen", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 10 letters (nearest by frequency rank).

recreation#6,729mechanisms#6,808navigation#6,814Portuguese#6,823

Similar misspelling depth

Headwords with a similar count of attested misspellings (17 here; floor ≥5).

magnificent17 variantsintermediate17 variantsidentifying17 variantsuncertainty17 variants

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

Source: FrequencyWords open word-frequency list