A small bump in the eyelid developed as a result of a blockage if oil gland is known as chalazion. The chalazion is formed in the glands that produce the fluid which helps in lubricating the eye. These glands are known as Meibomian glands. Approximately 100 of glands are present in the eyelid which is situated near the eyelashes.A chalazion is caused as a result of blockage of the duct that is responsible for draining one of these glands. The commonly observed symptoms of chalazion are increased tearing, sensitivity to light, tenderness of the eye and painful swelling of the eyelid.