Where does “zel-” come from?
zel- (Proto-Balto-Slavic) comes from Proto-Balto-Slavic zal-, from Proto-Indo-European ǵʰelh₃- — to flourish; green, yellow.
zel- (Proto-Balto-Slavic) comes from Proto-Balto-Slavic zal-, from Proto-Indo-European ǵʰelh₃- — to flourish; green, yellow.