Conjunctival vaccination is a medical procedure that involves administering a vaccine through the conjunctiva - the thin, transparent layer of tissue that covers the white part of the eye and lines the inside of the eyelid. There are different synonyms that can be used to describe this vaccination process, including ocular vaccination, eye drop vaccination, and mucosal vaccination. This type of vaccination is often used to protect against specific pathogens that enter the body through mucous membranes, such as the ones in the eyes, nose, and mouth. Conjunctival vaccination has been successful in preventing diseases such as polio, measles, and rubella.