腹を割って話し合おう。

abdomen; belly; stomach; womb; one's mind; one's real intentions; one's true motive; courage; nerve; willpower; generosity; magnanimity; feelings; emotions; wide middle part; bulging part; inside; interior; inner part; anti-node; counter for hard roe; counter for containers with bulging middles (pots, vases, etc.)

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to divide; to cut; to break; to halve; to separate; to split; to rip; to crack; to smash; to dilute

to discuss; to talk together