letterbox

noun

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

"letterbox" is a 9-letter English headword indexed on PlainSpell.

The verdict

“letterbox” is uncommon English (frequency #51,217 among 16,425 “L” headwords), classed as a noun. The kind of spelling people second-guess.

#51,217
frequency rank, English
16,425
“L” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A box into which mail is put.

Key facts for letterbox
PropertyValue
Headwordletterbox
LanguageEnglish
Part of speechNoun
Letters9
Frequency rank#51,217
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “letterbox” 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). letterbox lands here:

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

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

Rare enough to double-check

letterbox is uncommon English at frequency #51,217 among 16,425 “L” headwords, classed as anoun. Rarity is why readers land here mid-draft. 4 senses are on record.

Zero misspellings are on record for letterbox in our index, since its letter sequence doesn't invite the usual edit-distance slips. This entry stands alone in our confusable dataset, suggesting its spelling stands apart enough that readers rarely confuse it with something else.

Etymologically, the entry records: From letter + box. The correct English form is letterbox, spelled L-E-T-T-E-R-B-O-X.

Definition

  1. 1
    A box into which mail is put.
  2. 2
    A box into which mail is put.
  3. 3
    A hidden container that holds a logbook and rubber stamp, found by following clues as a form of recreation.
  4. 4
    A rectangular hole or slot.

Etymology

From letter + box.

This word in other languages

buzón(Español)boîte aux lettres(Français)Briefkasten(Deutsch)

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 "letterbox"?
"letterbox" is spelled L-E-T-T-E-R-B-O-X.
What does "letterbox" mean?
As a noun, "letterbox" means: A box into which mail is put.
What is the origin of the word "letterbox"?
From letter + box. 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 “letterbox”

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

  • The one correct English spelling is L-E-T-T-E-R-B-O-X - every other letter order is a misspelling in standard orthography.
  • Browse more English words and confusable pairs in the same reference. English words

Other uncommon English words near this rank

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