to boil food in liquid until it is cooked; to seethe or stew, especially meat
This is the ordinary Hebrew word for cooking something in hot liquid. Meat simmered in a pot, stew bubbling in a cauldron, the manna the Israelites gathered and cooked. It is the everyday verb of the kitchen, and of the sacrificial kitchen too, where priests boiled the portions of the offerings.
It stands in deliberate contrast to roasting over an open fire. The Passover lamb, for instance, was to be roasted, never boiled. Yet the word is flexible: a later account can use it broadly for preparing the Passover, and it is used once for cooking cakes, so it does not always mean strictly cooking in water. The steady core is bringing food to a done state by heat and moisture.
Because boiling is the plainest way to cook flesh, this one verb carries both the Bible's holiest scenes and its most horrifying. Priests boil the sacrifices in the temple kitchens; and in the depths of siege famine, mothers boil their own children.