The bottom or lowest part of an organ (especially the stomach, uterus, or eye), or land/estate in Roman law.
From Latin 'fundus' meaning bottom, base, or landed property. The term was used in Roman law for estates, and adopted into anatomy to describe the base of organs.
Medieval doctors borrowed the Latin term 'fundus' for the bottom of organs, and centuries later it's still the standard term—'fundus of the stomach' is what your doctor means by your stomach's base.
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