Where does “ajatusharha” come from?

ajatusharha (Finnish) comes from Finnish ajatus, from Finnish ajattaa, from Finnish ajaa, from Proto-Finnic ajadak, from Proto-Uralic aja-, from Proto-Indo-Iranian Háȷ́ati, from Proto-Indo-European h₂éǵeti, from Proto-Indo-European h₂eǵ- — to drive.

Ancestry of “ajatusharha”, step by step

ajatusharha traces back through two separate lines of ancestry.

via Finnish ajatus

StepLanguageWordMeaning
1Finnishajatusthought; idea
2FinnishajattaaTo have something driven
3Finnishajaato drive, ride, travel in a vehicle, transport in...
4Proto-Finnicajadakto go in a vehicle, to drive
5Proto-Uralicaja-to drive; to hunt, chase
6Proto-Indo-IranianHáȷ́atito drive, lead
7Proto-Indo-Europeanh₂éǵetito be driving
8Proto-Indo-Europeanh₂eǵ-to drive

via Finnish harha

StepLanguageWordMeaning
1Finnishharhaillusion, delusion, hallucination, chimera,...
2FinnishharhaanIllative singular form of harha; astray, amiss
Every word from Proto-Indo-European h₂eǵ-Every word from Proto-Indo-European h₂éǵetiEvery word from Proto-Indo-Iranian Háȷ́ati