For many medical terms the main body of the word indicates the organ or part of the body that is modified by a prefix or a suffix, or both. The combining forms for the words cardiomegaly, hepatomegaly, and splenomegaly are respectively:
cardio (heart)
hepato (liver)
spleno (spleen)
Each of these words is modified by a suffix which is made up of the combining form (mega = large) + a suffix ending (-ly) meaning characterized by.
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