Final answer:
Edema is swelling due to fluid accumulation in tissues, often associated with underlying medical issues and requires diagnosis to be treated effectively.
Step-by-step explanation:
The term for swelling or fluid accumulation in tissues is edema. Edema involves the excess water retention in the soft tissues of the body, which can present as swelling, an increase in the size of a limb, and tight, stretched skin. The condition is often indicative of an underlying medical issue, such as heart failure or renal failure, and can result from various factors, including circulatory deficits, side effects of medication, or injury. Determining the cause of edema is essential for treatment, with possible causes including hypertension, protein deficiency, or blockages in lymphatic vessels.