JMdict: 1632610

べし 【べし】

1. [aux] must; should; ought to
2. [aux] will (surely); be bound to; must
3. [aux] will (do); shall

Words often seen with this one: (experimental feature)

者 (15), 人 (13), 眠り (12), 死 (12), という (12), なる (10), ぐる (10), その (10)