īˈrisate transitive verb

To make iridescent

irisation /ī-ri-sāˈshən/ noun

irised /īˈrist/ adjective

Showing colours like the rainbow

iris diaphragm noun

An adjustable stop for a lens, giving a continuously variable hole

iris recognition or iris scanning noun

A security system which uses a digital camera to detect the unique marks on a person's iris and map these to information on a database in order to confirm the person's identity