noun · 4 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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/ˈlɪtməs/
Southern-England:Recorded audio is listed in the source snapshot.
rhymes with -ɪtməs
CMU ARPABET:L IH1 T M AH0 S
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 1
A dyestuff extracted from certain lichens, that changes color when exposed to pH levels greater than or less than certain critical levels.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
A simple test of acidity in a liquid using litmus, usually in the form of litmus paper.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
3
noun
Meaning 3
A simple test of any attribute; a litmus test.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
noun
Meaning 4
a coloring material (obtained from lichens) that turns red in acid solutions and blue in alkaline solutions; used as a very rough acid-base indicator
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: litmus test
Antonyms: none provided
Broader terms: acid-base indicator
History
Etymology
From Middle English litmose, lytmose, litemose, from Old Norse litmosi (“moss used for dyeing”), from lita (“to dye, stain”) + mosi (“moss”), the former from litr (“colour, dye, blee”), from Proto-Germanic *wlitiz, *wlituz (“appearance, blee”), from Proto-Indo-European *wel- (“to see”). Cognate with Old English wlite (“appearance, form, brightness, countenance”). More at moss.
Across languages
Translations
27 source translations are retained for this English entry.
Bulgarian:
лакмус
(lakmus)
— dyestuff from lichen
Chinese Mandarin:
石蕊
(shíruǐ)
— dyestuff from lichen
Czech:
lakmus
— dyestuff from lichen
Dutch:
lakmoes
— dyestuff from lichen
Finnish:
lakmus
— dyestuff from lichen
French:
tournesol
— dyestuff from lichen
Galician:
tornasol
— dyestuff from lichen
Georgian:
ლაკმუსი
(laḳmusi)
— dyestuff from lichen
German:
Lackmus
— dyestuff from lichen
Greek:
ηλιοτρόπιο
(iliotrópio)
— dyestuff from lichen
Hungarian:
lakmusz
— dyestuff from lichen
Italian:
tornasole
— dyestuff from lichen
Japanese:
リトマス
(ritomasu)
— dyestuff from lichen
Korean:
리트머스
(riteumeoseu)
— dyestuff from lichen
Latin:
lacmus
— dyestuff from lichen
Macedonian:
лакмус
(lakmus)
— dyestuff from lichen