Where does “kostoisku” come from?

kostoisku (Finnish) comes from Finnish isku, from Finnish -u, from Proto-Finnic -u — Forms nouns from adjectives, nouns.

kostoisku (Finnish): retaliation, retaliatory attack, revenge attack

Definitions

  1. retaliation, retaliatory attack, revenge attack

Ancestry of “kostoisku”, step by step

kostoisku traces back through two separate lines of ancestry.

via Finnish isku

StepLanguageWordMeaning
1Finnishiskuhit, blow; impact; attentat, attack, strike, raid
2Finnish-uForms nouns from verbs. Most common with "e"- and...
3Proto-Finnic-uForms nouns from adjectives, nouns

via Finnish kosto

StepLanguageWordMeaning
1Finnishkostorevenge, vengeance
2Finnishkostaato avenge, revenge, take revenge, get back at (on); to retaliate (to)
3Proto-Finnickostadak? to turn, to turn back
Every word from Proto-Finnic -uEvery word from Finnish -uEvery word from Finnish isku
kostoisku — Etymology, Origin & Word History | Etymology Explorer