Main Entry: oc·clu·sion

Pronunciation: \ə-ˈklü-zhən\

Function: noun

Etymology: Latin occludere

Date: circa 1645

1 : the act of occluding : the state of being occluded: as a : the complete obstruction of the breath passage in the articulation of a speech sound b : the bringing of the opposing surfaces of the teeth of the two jaws into contact; also : the relation between the surfaces when in contact c : the inclusion or sorption of gas trapped during solidification of a material
2 : the front formed by a cold front overtaking a warm front and lifting the warm air above the earth's surface