легковерный означает в английский

credulous▼(excessively ready to believe things)
adjective
[UK: ˈkre.djʊ.ləs] [US: ˈkre.djʊ.ləs]

gullible▼(easily deceived or duped, naive)
adjective
[UK: ˈɡʌ.lɪb.l̩] [US: ˈɡʌ.ləb.l̩]

dupe [dupes]▼(deceived person)
noun
[UK: djuːp] [US: ˈduːp]