From Longman Dictionary of Contemporary Englishthe bowels of somethingthe bowels of somethingliteraryALBOTTOM the lowest or deepest part of somethingthe bowels of the earth (=deep under the ground) → bowel
Examples from the Corpus
the bowels of the earth• The bell boomed as though it came from the bowels of the earth.• The Iron Rock is a core of molten iron vomited from the bowels of the earth during some incalculably ancient upheaval.• Cower in the bowels of the earth from it, and pull the bedclothes over your head.• But the third, deep in the bowels of the earth, was kept mysteriously locked at all times.• Tony was well briefed before we descended to the bowels of the earth. 