Borrowing from a Sami language (compare Southern Sami gaasoe (cold mist)), from Proto-Uralic *käsä (dew).[1] Originally a dialect word meaning 'mist, fog', adopted as an equivalent of gas by Finnish physician and author Samuel Roos in 1845, with influence from Dutch gas (whence words in many other European languages, such as English gas).[2]


  • IPA(key): /ˈkɑːsu/, [ˈkɑːs̠u]
  • Rhymes: -ɑːsu
  • Syllabification(key): kaa‧su



  1. gas (state of matter)
  2. gas pedal
    Synonym: kaasupoljin
  3. (colloquial) laughing gas (particularly as an intoxicant)
    Synonym: ilokaasu
  4. (idiomatic, informal) olla kaasussa: to be drunk
    Synonym: see humalassa


Inflection of kaasu (Kotus type 1/valo, no gradation)
nominative kaasu kaasut
genitive kaasun kaasujen
partitive kaasua kaasuja
illative kaasuun kaasuihin
singular plural
nominative kaasu kaasut
accusative nom. kaasu kaasut
gen. kaasun
genitive kaasun kaasujen
partitive kaasua kaasuja
inessive kaasussa kaasuissa
elative kaasusta kaasuista
illative kaasuun kaasuihin
adessive kaasulla kaasuilla
ablative kaasulta kaasuilta
allative kaasulle kaasuille
essive kaasuna kaasuina
translative kaasuksi kaasuiksi
instructive kaasuin
abessive kaasutta kaasuitta
comitative kaasuineen
Possessive forms of kaasu (type valo)
possessor singular plural
1st person kaasuni kaasumme
2nd person kaasusi kaasunne
3rd person kaasunsa

Derived termsEdit


See alsoEdit


  1. ^ Aikio, Ante. 2009. The Saami loanwords in Finnish and Karelian. PhD thesis. University of Oulu.
  2. ^ Itkonen, Erkki; Kulonen, Ulla-Maija, editors (1992–2000) Suomen sanojen alkuperä [The origin of Finnish words]‎[1] (in Finnish), [note: linked online version also includes some other etymological sources], Helsinki: Institute for the Languages of Finland/Finnish Literature Society, →ISBN