ACLU

name

"aclu" is a 4-letter English headword indexed on PlainSpell.

The verdict

“ACLU” is a moderately-common English word, ranked #21,127 in English word frequency and used as a proper noun.

#21,127
frequency rank, English
4
letters
5
tracked misspellings
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Initialism of American Civil Liberties Union.

Visual similarity to commonly confused words

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

ACLU vs AL
50% similar
ACLU vs AU
50% similar
ACLU vs all
0% similar

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

Key facts for ACLU
PropertyValue
HeadwordACLU
LanguageEnglish
Part of speechProper noun
Letters4
Frequency rank#21,127
Misspellings tracked5
Confusable pairs20
SourceWiktionary (kaikki.org)

Where “ACLU” 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). ACLU 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 ACLU is 4 letters long, classified as a proper noun. Corpus data places it at rank #21,127 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "Initialism of American Civil Liberties Union.".

Our generated misspelling index lists 5 likely wrong-spelling variants for ACLU, with forms such as "acclu", "acllu", and "acul". 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 20 confusable-pair relationships, "AL", "AU", "all", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

No borrowing history is documented for this entry, so any spelling logic here comes from how the word's sounds map to letters, not a documented origin story. The correct English form is ACLU, spelled A-C-L-U.

Definition

  1. 1
    Initialism of American Civil Liberties Union.

Common misspellings

Also misspelled as: acclu,acllu,acul,alcu,calu

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of ACLU - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.

acclu1acllu1acul2alcu2calu2
Edit distance from "ACLU"

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 "ACLU"?
"ACLU" is spelled A-C-L-U.
What does "ACLU" mean?
As a proper noun, "ACLU" means: Initialism of American Civil Liberties Union.
What words are commonly confused with "ACLU"?
"ACLU" is commonly confused with "AL", "AU", "all". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
What language does "ACLU" come from?
"ACLU" is a English word. PlainSpell covers definitions, pronunciations, and spelling data across English, Spanish, Portuguese, French, and German.
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 “ACLU”

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

  • The one correct English spelling is A-C-L-U - every other letter order is a misspelling in standard orthography.
  • Don't mix it up with “AL” - see the side-by-side comparison. ACLU vs AL
  • 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