vaikuttaa

vaiku- +‎ -ttaa, with a root of unknown origin. The root word vaikku (“power, effectiveness”) can indeed be found in dialects, but it may be a back-formation. Theories about the root include that it is a borrowing from Proto-Norse [script needed] (*kwaikwō) (compare Old Norse kveika (“fuel”)) and that it is a borrowing from Baltic (compare Lithuanian viẽkas (“power, vitality”)). It is unknown whether it is related to vaikku (“earwax”), but if so, the link may be a reference to the supposed healing powers of earwax (in folk medicine).

• IPA^(key): /ˈʋɑi̯kutːɑːˣ/, [ˈʋɑ̝i̯kut̪ːɑ̝ː(ʔ)]
• Rhymes: -ɑikutːɑː
• Syllabification^(key): vai‧kut‧taa

vaikuttaa (intransitive)

1. to influence, have an influence on, affect, have an effect on, impact, have an impact on (+ illative)

   Rankat sateet vaikuttivat selvästi järven vedenpinnan korkeuteen.

   The heavy rainfall clearly had an effect on the water level of the lake.

   Tämä vaikuttaa myös sinuun.

   This will affect you too.

2. to have an effect on, act, work (+ illative)

   alkaa vaikuttaa ― to take effect, start working

   Vaikuttiko antibiootti? / Kuinka nopeasti antibiootit vaikuttavat?

   Did the antibiotic have any effect? / How fast do antibiotics take effect?

3. to appear (to be), seem (to be) (to be (adjective/participle) = ablative/allative, to do = genitive of the present active participle, to have done = genitive of the past active participle)

   Synonym: näyttää

   Hän vaikuttaa iloiselta.

   S/he seems to be happy.

   Hänellä vaikutti olevan kiire.

   It appears he/she was busy.

   Hänellä vaikutti olleen kiire.

   It appears he/she had been busy.

4. (idiomatic, informal) to act as, to work as, to do (+ essive) (to have as one's job)

   Hän vaikutti muutamia vuosia opettajana Oulussa.

   For a few years, s/he worked as a teacher in Oulu.

   Missä sinä nykyään vaikutat?

   What are you doing nowadays?

5. (military) to fire for effect

• (to seem, appear):
  • With verbs, either the present or past active participle may be used, and there is a difference between them (as can be seen in the above usage examples).
  • With verbs, the case of the 'subject' will match that of the verb that is used with vaikuttaa. For example, in the above examples, hänellä is in the adessive case, because olla kiire (“to be busy”, literally “to have a hurry”) takes the adessive case for its 'subject'.

• (to act as): toimia

• “vaikuttaa”, 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 2023-07-04

• kaatuivat, kuivattaa