Dryness of the eye related to deficiency of the tear film components (aqueous, mucin, or lipid), lid surface abnormalities, or epithelial abnormalities. Keratoconjunctivitis sicca often results in a scratchy or sandy sensation (foreign body sensation) in the eyes, and may also be associated with itching, inability to produce tears, photosensitivity, redness, pain, and difficulty in moving the eyelids. The phenotype is Human Phenotype Ontology term HP_0001097 (Keratoconjunctivitis sicca). Also known as: Dry eyes, Keratitis sicca, Xerophthalmia.