occlusion

Concise Oxford English Dictionary © 2008 Oxford University Press:
occlusion/əˈkluːʒn/

▶noun

• 1 Medicine the blockage or closing of a blood vessel or hollow organ.

• 2 Meteorology a process by which the cold front of a rotating low-pressure system catches up the warm front, so that the warm air between them is forced upwards.

• 3 Dentistry the position of the teeth when the jaws are closed.

– derivatives
occlusive adjective.