plug / pləg/ • n. 1. an obstruction blocking a hole, pipe, etc.: somewhere in the pipes there is a plug of ice blocking the flow. ∎  a circular piece of metal, rubber, or plastic used to stop the drain of a bathtub or basin and keep the water in it. ∎  inf. a baby's pacifier. ∎  a mass of solidified lava filling the neck of an old volcano. ∎  (in gardening) a young plant or clump of grass with a small mass of soil protecting its roots, for planting in the ground.2. a device for making an electrical connection, esp. between an appliance and a power supply, consisting of an insulated casing with metal pins that fit into holes in an outlet. ∎ short for spark plug.3. inf. a piece of publicity promoting a product, event, or establishment: he threw in a plug, boasting that the restaurant offered many entrées for under $5.4. a piece of tobacco cut from a larger cake for chewing. ∎  (also plug tobacco) tobacco in large cakes designed to be cut for chewing.5. Fishing a lure with one or more hooks attached.6. short for fireplug.7. inf. a tired or old horse.• v. (plugged, plug·ging) [tr.] 1. block or fill in (a hole or cavity): trucks arrived loaded with gravel to plug the hole and clear the road | fig. the new sanctions are meant to plug the gaps in the trade embargo. ∎  insert (something) into an opening so as to fill it: the baby plugged his thumb into his mouth.2. inf. mention (a product, event, or establishment) publicly in order to promote it: during the show he plugged his new record.3. inf. shoot or hit (someone or something).4. [intr.] inf. proceed steadily and laboriously with a journey or task: during the years of poverty, he plugged away at his writing.PHRASES: pull the plugsee pull.PHRASAL VERBS: plug something in connect an electrical appliance to a power supply by inserting a plug into an outlet.plug into (of an electrical appliance) be connected to another appliance by a plug inserted in an outlet. ∎  gain or have access to a system of computerized information: we plug into the research facilities available at the institute. ∎ fig. become knowledgeable about and involved with: the good thing about this job is that I'm plugged into what's going on.DERIVATIVES: plug·ger n.

plug piece of wood, etc. to stop a hole, etc. XVII; cock of water-pipe; tobacco pressed into a cake XVIII. — MLG., MDu. plugge (Du. plug); of unkn. orig.
Hence plug vb. XVII.

plug See VOLCANIC PLUG.