ośmielić (Polish) comes from Polish śmiały, from Proto-Slavic sъmělъ, from Proto-Slavic sъměti, from Proto-Slavic sъ-, from Proto-Indo-European h₁su-, from Proto-Indo-European h₁wes- — good; to be cheerful, happy; to eat, to feast.
ośmielić (Polish): to embolden, to encourage