con·stric·tor / kənˈstriktər/ • n. 1. a snake (families Boidae and Pythonidae, and some members of other families, esp. Colubridae) that kills by coiling around its prey and asphyxiating it. 2. (also constrictor muscle) Anat. a muscle whose contraction narrows a vessel or passage. ∎  each of the muscles that constrict the pharynx.

constrictor (kŏn-strik-ter) n. any muscle that compresses an organ or causes a hollow organ or part to contract.