# radon
## English
### Etymology

Contraction of radium emanation, since the element appears in the radioactive decay of radium.

### Pronunciation

* enPR: rā'dŏn, IPA: /ˈɹeɪdɒn/
* Audio (Southern England):(file)

### Noun

radon (uncountable)
* The chemical element (symbol Rn, formerly Ro) with atomic number 86. It is an odorless, colorless, chemically inert but radioactive noble gas.
* Radon-222 ($^{222}$$_{86}$Rn), the most stable isotope of said element.

#### Usage notes

The isotopes $^{222}$Rn, $^{220}$Rn, and $^{219}$Rn were discovered independently, and were called radon (Rn), thoron (Tn), and actinon (An) respectively. In 1957, it was finally decided that the name radon should refer to the element in general, regardless of isotope. Thoron still survives as a name for $^{220}$Rn today; actinon is mostly obsolete, because $^{219}$Rn is short-lived.

#### Synonyms

* emanation (obsolete)
* niton (obsolete)
* exradio (archaic)
* radeon (obsolete)
* radium emanation (obsolete)

#### Hyponyms

* actinon (An; radon-219)
* radon (Rn; radon-222)
* thoron (Tn; radon-220)

#### Derived terms

* eka-radon
* radon difluoride
* radon fluoride
* radon seed

#### Related terms

* radium

#### Translations

    The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

### See also

* actinon
* radium emanation

### References

* Radon on the British Royal Society of Chemistry's online periodic table
* ↑ Thornton, Brett F., Burdette, Shawn C. (2013 August 22) “Recalling radon's recognition”, in Nature Chemistry, volume 5, number 9, →Bibcode, →DOI, →PMID, page 804

### Anagrams

* Ardon, Daron, rando, Andro, Ronda, Norad, NORAD, Doran, andro, Drona, andor, norad, Nador, and/or, Nardo, adorn, andro-

## Afrikaans
### Pronunciation

* Audio:(file)
* Hyphenation: ra‧don

### Noun

radon (uncountable)
* radon

#### Hypernyms

* edelgas

## Basque
### Etymology

From Spanish radón.

### Pronunciation

* Audio:(file)
* IPA: /radon/, [ra.ð̞õ̞n]

### Noun

radon inan
* radon

#### Declension
### Further reading

* “radon”, in Euskaltzaindiaren Hiztegia [Dictionary of the Basque Academy] (in Basque), Euskaltzaindia [Royal Academy of the Basque Language]

## Crimean Tatar

Other scripts :
| Cyrillic | радон |
| Roman | |

### Etymology

Borrowed from Russian радон (radon).

### Noun

radon
* radon

#### Declension
### References

* Mirjejev, V. A., Usejinov, S. M. (2002) Ukrajinsʹko-krymsʹkotatarsʹkyj slovnyk [Ukrainian – Crimean Tatar Dictionary]‎, Simferopol: Dolya, →ISBN
* “radon”, in Luğatçıq (in Russian)

## Czech
### Pronunciation

* IPA: [ˈradon]
* IPA: [ˈradoːn]

### Noun

radon m inan
* radon

#### Declension
## Danish
### Etymology

From Latin radium +‎ -on.

### Noun

radon n (singular definite radonet, not used in plural form)
* radon

#### Declension
### References

* “radon” in Den Danske Ordbog

## Dutch
### Pronunciation

* Audio:(file)

### Noun

radon n (uncountable)
* radon

## Esperanto
### Noun

radon
* accusative singular of rado

## Finnish
### Etymology

From English radon.

### Pronunciation

* IPA: /ˈrɑ(ː)don/, [ˈrɑ̝(ː)do̞n]
* Rhymes: -ɑdon
* Hyphenation: ra‧don

### Noun

radon
* radon

#### Declension

Possessive forms of radon (Kotus type 6/paperi, no gradation) :
first-person singular possessor
singular
plural
nominative
radonini
radonini
accusative
nom.
radonini
radonini
gen.
radonini
genitive
radonini
radonieni radoneideni radoneitteni
partitive
radoniani
radoneitani radonejani
inessive
radonissani
radoneissani
elative
radonistani
radoneistani
illative
radoniini
radoneihini
adessive
radonillani
radoneillani
ablative
radoniltani
radoneiltani
allative
radonilleni
radoneilleni
essive
radoninani
radoneinani
translative
radonikseni
radoneikseni
abessive
radonittani
radoneittani
instructive
comitative
—radoneineni
second-person singular possessor
singular
plural
nominative
radonisi
radonisi
accusative
nom.
radonisi
radonisi
gen.
radonisi
genitive
radonisi
radoniesi radoneidesi radoneittesi
partitive
radoniasi
radoneitasi radonejasi
inessive
radonissasi
radoneissasi
elative
radonistasi
radoneistasi
illative
radoniisi
radoneihisi
adessive
radonillasi
radoneillasi
ablative
radoniltasi
radoneiltasi
allative
radonillesi
radoneillesi
essive
radoninasi
radoneinasi
translative
radoniksesi
radoneiksesi
abessive
radonittasi
radoneittasi
instructive
comitative
—radoneinesi
first-person plural possessor
singular
plural
nominative
radonimme
radonimme
accusative
nom.
radonimme
radonimme
gen.
radonimme
genitive
radonimme
radoniemme radoneidemme radoneittemme
partitive
radoniamme
radoneitamme radonejamme
inessive
radonissamme
radoneissamme
elative
radonistamme
radoneistamme
illative
radoniimme
radoneihimme
adessive
radonillamme
radoneillamme
ablative
radoniltamme
radoneiltamme
allative
radonillemme
radoneillemme
essive
radoninamme
radoneinamme
translative
radoniksemme
radoneiksemme
abessive
radonittamme
radoneittamme
instructive
comitative
—radoneinemme
second-person plural possessor
singular
plural
nominative
radoninne
radoninne
accusative
nom.
radoninne
radoninne
gen.
radoninne
genitive
radoninne
radonienne radoneidenne radoneittenne
partitive
radonianne
radoneitanne radonejanne
inessive
radonissanne
radoneissanne
elative
radonistanne
radoneistanne
illative
radoniinne
radoneihinne
adessive
radonillanne
radoneillanne
ablative
radoniltanne
radoneiltanne
allative
radonillenne
radoneillenne
essive
radoninanne
radoneinanne
translative
radoniksenne
radoneiksenne
abessive
radonittanne
radoneittanne
instructive
comitative
—radoneinenne
third-person possessor
singular
plural
nominative
radoninsa
radoninsa
accusative
nom.
radoninsa
radoninsa
gen.
radoninsa
genitive
radoninsa
radoniensa radoneidensa radoneittensa
partitive
radoniaan radoniansa
radoneitaan radonejaan radoneitansa radonejansa
inessive
radonissaan radonissansa
radoneissaan radoneissansa
elative
radonistaan radonistansa
radoneistaan radoneistansa
illative
radoniinsa
radoneihinsa
adessive
radonillaan radonillansa
radoneillaan radoneillansa
ablative
radoniltaan radoniltansa
radoneiltaan radoneiltansa
allative
radonilleen radonillensa
radoneilleen radoneillensa
essive
radoninaan radoninansa
radoneinaan radoneinansa
translative
radonikseen radoniksensa
radoneikseen radoneiksensa
abessive
radonittaan radonittansa
radoneittaan radoneittansa
instructive
comitative
—radoneineen radoneinensa :

#### Derived terms

* radonfluoridi
* radonmittari
* radonmittaus
* radonpitoinen

#### See also

* raadon

### Further reading

* “radon”, in Kielitoimiston sanakirja [Dictionary of Contemporary Finnish]‎ (in Finnish) (online dictionary, continuously updated), Kotimaisten kielten keskuksen verkkojulkaisuja 35, Helsinki: Kotimaisten kielten tutkimuskeskus (Institute for the Languages of Finland), 2004–, retrieved 2023-07-03

### Anagrams

* andro-

## French
### Pronunciation

* IPA: /ʁa.dɔ̃/
* Audio:(file)
* Rhymes: -ɔ̃

### Noun

radon m (uncountable)
* radon

### Further reading

* “radon”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.

### Anagrams

* rando

## Galician
### Noun

radon m (uncountable)
* radon

## Hungarian
### Pronunciation

* IPA: [ˈrɒdon]
* Hyphenation: ra‧don
* Rhymes: -on

### Noun

radon (usually uncountable, plural radonok)
* radon

#### Declension
## Icelandic
### Noun

radon n (genitive singular radons, no plural)
* radon (chemical element)

#### Declension
## Italian
### Pronunciation

* IPA: /ˈra.don/
* Rhymes: -adon
* Hyphenation: rà‧don

### Noun

radon m (invariable)
* (chemistry) radon

### Anagrams

* Andro, Nardò, Rando, andro-, andrò, nardo, ronda

## Japanese
### Romanization

radon
* Rōmaji transcription of ラドン

## Latin
### Pronunciation

* (Classical Latin) IPA: /ˈra.don/, [ˈräd̪ɔn]
* (modern Italianate Ecclesiastical) IPA: /ˈra.don/, [ˈräːd̪on]

### Noun

radon n (genitive radī); second declension
* radon

#### Declension

Second-declension noun (neuter, Greek-type).

## Malay
### Etymology

From English radon.

### Pronunciation

* IPA: [radɔn], [redɔn]
* Rhymes: -dɔn, -ɔn

### Noun

radon
* radon (chemical element)

## Maltese
### Etymology

Borrowed from Italian radon.

### Pronunciation

* IPA: /ˈraː.dɔn/

### Noun

radon m
* (chemistry) radon (chemical element)

## Polish
### Etymology

Learned borrowing from New Latin radon.

### Pronunciation

* IPA: /ˈra.dɔn/
* Audio 1:(file)
* Audio 2:(file)
* Rhymes: -adɔn
* Syllabification: ra‧don

### Noun

radon m inan (related adjective radonowy)
* radon (chemical element (symbol Rn, formerly Ro) with atomic number 86; a colorless, odorless, chemically inert but radioactive noble gas)

#### Declension
### Further reading

* radon in Polish dictionaries at PWN
* radon in PWN's encyclopedia

## Romanian
### Etymology

Borrowed from French radon.

### Noun

radon n (uncountable)
* radon

#### Declension
## Serbo-Croatian
### Noun

radon m (Cyrillic spelling радон)
* radon

## Slovene
### Pronunciation

* IPA: /ráːdɔn/, /radóːn/

### Noun

radọ̑n or radón m inan
* radon

#### Inflection
### Further reading

* “radon”, in Slovarji Inštituta za slovenski jezik Frana Ramovša ZRC SAZU (in Slovene), 2014–2025

## Swedish
### Pronunciation

* IPA: /raˈdoːn/
* Audio:(file)

### Noun

radon n (uncountable)
* radon

#### Declension
### References

* radon in Svensk ordbok (SO)
* radon in Svenska Akademiens ordlista (SAOL)
* radon in Svenska Akademiens ordbok (SAOB)
* Svensk MeSH

### Anagrams

* andor, donar, ordna, rodna

## Turkish
### Etymology

Borrowed from French radon.

### Pronunciation

* Audio:(file)

### Noun

radon (definite accusative radonu, plural radonlar)
* radon

#### Declension
### Further reading

* “radon”, in Turkish dictionaries, Türk Dil Kurumu

## Welsh
### Etymology

Borrowed from English radon.

### Pronunciation

* (North Wales) IPA: /ˈradɔn/
* (South Wales) IPA: /ˈra(ː)dɔn/
* Rhymes: -adon

### Noun

radon m (uncountable, not mutable)
* radon

### References

* R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), “radon”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies