What term refers to a chronic middle ear disorder where fluid becomes thick or pus-like?

The term that denotes a chronic middle ear disorder characterized by the presence of thick or pus-like fluid is indeed mucoid otitis media. This condition typically involves the effusion of thickened mucus within the middle ear space, which can occur as a result of ongoing inflammation or infection. It often leads to symptoms such as hearing loss and discomfort.

In the context of the other options, serous otitis media refers to a condition where there is a clear, watery fluid accumulation in the middle ear, not necessarily thick or pus-like. Otosclerosis is a different issue that involves abnormal bone growth in the middle ear, affecting hearing but not characterized by fluid accumulation. Adhesive otitis media, on the other hand, involves a retraction of the tympanic membrane and can lead to a sticky situation in the middle ear, but does not specifically refer to the presence of thick or pus-like fluid. Thus, mucoid otitis media is the term that accurately encompasses the described characteristics.