What medical term refers to swelling, especially in body tissues?

The term that refers specifically to swelling, particularly in body tissues, is "edema." Edema occurs when excess fluid accumulates in the interstitial spaces of tissues, leading to visible or palpable swelling. This condition can happen in various parts of the body and may be caused by factors such as injury, inflammation, and certain medical conditions that affect fluid balance.

In contrast, infection refers to the invasion of the body by pathogens, which can lead to symptoms such as pain, redness, and sometimes swelling, but the primary focus is on the presence of microorganisms. Inflammation is a broader term that describes the body's response to injury or infection, which can indeed include swelling among other symptoms like heat, redness, and pain. Necrosis, on the other hand, refers to the death of cells or tissues and does not inherently imply swelling, although necrotic tissue can lead to associated edema in surrounding areas. Thus, edema is the most accurate term when specifically addressing the concept of swelling in body tissues.