1. To stop, to close up, or to obstruct an opening, an orifice, or a passage: Caron was told that thick makeup can occlude the pores of her facial skin.

Ted's doctor told him that the blood vessel in his leg was occluding and that it was necessary that surgery be done so the blood could flow properly again.
2. To shut something in: The city has been occluding some areas with a significant number of apartment buildings.
3. To close onto or to align the upper and the lower teeth in proper positions for chewing or for being in their normal contacts when the mouth is closed: Maurice had to go to the dentist to occlude his molars so he could eat properly after some of them were extracted and replaced with a partial denture which could be removed for cleaning and then replaced in his mouth.
4. Etymology: from Latin occludere, "to close up"; from ob-, " toward, against, before" + claudere, "to close".