Bileve

To believe or accept something as true, especially in archaic or dialectal usage; an old-fashioned form of 'believe'.

Middle English bileven, from Old English belyfan, combining be- (prefix meaning 'make' or 'cause') and leaf/lief (meaning 'to allow' or 'to remain'). The meaning evolved from 'to allow to remain' to 'to accept as true' through Old Norse and Germanic influences.