The term 'CONGESTION SITE' can be summarized as a location where congestion is likely to occur. The crossword solution for this term is 'SINUS', which refers to the sinuses in the human body. Sinuses are hollow cavities in the skull that are connected to the nasal passages and are filled with air. When these cavities become blocked or inflamed, it can cause congestion in the nose and throat, leading to difficulty breathing.