This is the 673rd most frequent Estonian word.
muidu
"Otherwise" or "for free."
Muidu is used to mean 'otherwise,' offering an alternative or consequence.
Ma pean minema, muidu ma hilinen.
I have to go, otherwise I will be late.
Muidu is used in this context to indicate an accompanying action or state.
Ta tegi selle ära muidu mängides.
He did it while playing otherwise.
Muidu here conveys 'otherwise' as a condition for providing information.