Lacrimation

The secretion and discharge of tears from the lacrimal glands, either at a normal basal rate or in excessive amounts secondary to ocular or systemic stimuli. Possible causes are ocular irritation (dust, sand, wind, bright light, onions), dry eye syndrome, allergies, infection/inflammation (conjunctivitis, blepharitis), blocked nasolacrimal duct, ectropion, and entropion.