Dacryocyst, also known as nasolacrimal sac, is a part of the human eye that collects tears. Synonyms for this word include lacrimal sac, tear sac, and lacrimal pouch. In medical terminology, the dacryocyst is the dilated end of the tear duct, where tears collect before draining into the nasal cavity. Other synonyms for this term include lacrimal gland and tear gland, which are responsible for producing tears. The word dacryocyst is derived from the Greek words dakruon, meaning "tear," and kystis, meaning "bladder." It is an important part of the eye that helps to maintain healthy vision and lubrication.