A head cold is a common illness caused by a viral infection of the upper respiratory system. It is characterized by symptoms such as a runny or stuffy nose, sneezing, coughing, and sore throat. The two crossword solutions for the term 'head cold' are 'rheum' (5 letters) and 'sniffles' (8 letters). Rheum is a thin, watery discharge from the nose and eyes that is often associated with a head cold. Sniffles is another term for a runny nose, which is also a common symptom of a head cold.