בֶּטֶן beṭen (H990)

the belly, especially the womb; also the bosom or body of anything

1) belly, womb, body 1a) belly, abdomen 1a1) as seat of hunger 1a2) as seat of mental faculties 1a3) of depth of Sheol (fig.) 1b) womb

from an unused root probably meaning to be hollow;