leptospirosis

noun

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

"leptospirosis" is a 13-letter English headword indexed on PlainSpell.

The verdict

“leptospirosis” is uncommon English (frequency #95,074 among 16,425 “L” headwords), classed as a noun. The kind of spelling people second-guess.

#95,074
frequency rank, English
16,425
“L” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An acute, infectious, febrile disease of both humans and animals, caused by spirochetes of the genus Leptospira.

Key facts for leptospirosis
PropertyValue
Headwordleptospirosis
LanguageEnglish
Part of speechNoun
Letters13
Frequency rank#95,074
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “leptospirosis” 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). leptospirosis 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

leptospirosis is uncommon English at frequency #95,074 among 16,425 “L” headwords, classed as anoun. Rarity is why readers land here mid-draft. Gloss: "An acute, infectious, febrile disease of both humans and animals, caused by spirochetes of the genus Leptospira.".

leptospirosis doesn't appear in our generated misspelling index, suggesting the orthography follows predictable English patterns. Our confusable-pair dataset has no match for it, since no other headword is close enough in sound or shape to pair with it.

Etymologically, the entry records: From Leptospira + -osis. The correct English form is leptospirosis, spelled L-E-P-T-O-S-P-I-R-O-S-I-S.

Definition

  1. 1
    An acute, infectious, febrile disease of both humans and animals, caused by spirochetes of the genus Leptospira.

Etymology

From Leptospira + -osis.

Synonyms

Weil’s diseasecanicola fevercanefield fevernanukayami fever7-day feverrat catcher's yellowsFort Bragg feverblack jaundicepretibial feverrat fever

This word in other languages

leptospirose(Français)Leptospirose(Deutsch)leptospirose(Português)

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 "leptospirosis"?
"leptospirosis" is spelled L-E-P-T-O-S-P-I-R-O-S-I-S.
What does "leptospirosis" mean?
As a noun, "leptospirosis" means: An acute, infectious, febrile disease of both humans and animals, caused by spirochetes of the genus Leptospira.
What is the origin of the word "leptospirosis"?
From Leptospira + -osis. 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 “leptospirosis”

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

  • The one correct English spelling is L-E-P-T-O-S-P-I-R-O-S-I-S - 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