Inflammation of the ethmoid sinus that typically lasts beyond eight weeks. It is caused by infections, allergies, and the presence of sinus polyps or a deviated septum. Signs and symptoms include headache, nasal discharge, swelling in the face, dizziness, and breathing difficulties. The disease is Monarch Disease Ontology entry MONDO_0004757 (chronic ethmoidal sinusitis). Also known as: chronic ethmoid sinusitis, ethmoid sinusitis, chronic, ethmoidal sinusitis - chronic.