tap¹ / tap/ • n. 1. a device by which a flow of liquid or gas from a pipe or container can be controlled. ∎  a device connected to a telephone used for listening secretly to someone's conversations. ∎  an act of listening secretly to someone's telephone conversation. ∎  (also tap·ping) an electrical connection made to some point between the end terminals of a transformer coil or other component.2. an instrument for cutting a threaded hole in a material.3. Brit. a taproom.• v. (tapped, tap·ping) [tr.] 1. draw liquid through the tap or spout of (a cask, barrel, or other container): hoarse chatter of tests they had aced and kegs they had tapped. ∎  draw (liquid) from a cask, barrel, or other container: the butlers were tapping new and old ale. ∎  (often be tapped) connect a device to (a telephone) so that conversation can be listened to secretly: the telephones were tapped by the state security police. ∎ inf. obtain money or information from (someone): he considered whom he could tap for information. ∎  exploit or draw a supply from (a resource): clients from industry seeking to tap Philadelphia's resources of expertise | [intr.] these magazines have tapped into a target market of consumers. ∎  draw sap from (a tree) by cutting into it.2. cut a thread in (something) to accept a screw.PHRASES: on tap ready to be poured from a tap. ∎ inf. freely available whenever needed. ∎ inf. on schedule to occur.DERIVATIVES: tap·pa·ble adj.tap² • v. (tapped, tap·ping) [tr.] 1. strike (someone or something) with a quick light blow or blows: one of my staff tapped me on the shoulder. ∎  strike (something) against something else with a quick light blow or blows: Gloria was tapping her feet in time to the music. ∎  (tap something out) produce (a rhythm) with a series of quick light blows on a surface: drums that tapped out a rumba beat. ∎  write or enter (something) using a keyboard or keypad: he tapped out a few words on the keyboard.2. (usu. be tapped) inf. designate or select (someone) for a task or honor, esp. membership in an organization or committee: he had been tapped earlier to serve in Costa Rica.• n. 1. a quick light blow or the sound of such a blow.2. tap dancing. ∎  a piece of metal attached to the toe and heel of a tap dancer's shoe to make a tapping sound.3. (taps) [treated as sing. or pl.] a bugle call for lights to be put out in army quarters. ∎  a similar call sounded at a military funeral.DERIVATIVES: tap·per n.