53%RatingSave Gender Masculine Usage Finnish, Finnish Mythology Pronounced Pron. OOK-ko(Finnish) [key·IPA] Meaning & History Means "old man" in Finnish. In Finnish mythology Ukko is the god of the sky and thunder. Name DaysName Days? Finland: April 4 Categories agricultural deities, gods, mythology, old people, sky deities, supreme gods, thunder deities, weather, word names Entry updated December 3, 2014