In medical parlance, swelling, turgescence or tumefaction is a transient abnormal enlargement of a body part or area not caused by proliferation of cells.It is caused by accumulation of fluid in tissues. It can occur throughout the body (generalized), or a specific part or organ can be affected (localized).welling is considered one of the five characteristics of inflammation; along with pain, heat, redness, and loss of function. In a general sense, the suffix -megaly is used to indicate a growth, as in hepatomegaly, acromegaly, and splenomegaly.