важнейший znamená v Angličtina

paramount▼(of the highest importance)
adjective
[UK: ˈpæ.rə.maʊnt] [US: ˈpe.rə.ˌmɑːwnt]

prime▼(first in importance, degree, or rank)
adjective
[UK: praɪm] [US: ˈpraɪm]