- space filled with matter
- a full or general assembly, as of all members of a legislative body
- an enclosed volume of gas under greater pressure than that surrounding the container
- the state of this
Origin of plenumModern Latin ; from L, neuter of plenus, full
nounpl. ple·nums or ple·na
- An assembly or meeting with all members present.
- A condition, space, or enclosure in which air or other gas is at a pressure greater than that of the outside atmosphere.
- The condition of being full; fullness.
- A space completely filled with matter.
- A space lying above the ceiling in a building but below the next floor, especially one allowing movement of air between parts of the building.
Origin of plenumLatin pl&emacron;num (spatium), full (space), neuter of pl&emacron;nus; see pel&schwa;-1 in Indo-European roots.
(plural plenums or plena)
- (physics) A space that is completely filled with matter.
- (figuratively) A state of fullness, a great quantity (of something).
- A legislative meeting (especially of the Communist Party) in which all members are present.
- An enclosed space having greater than atmospheric pressure.
- The space above a false ceiling used for cables, ducts etc.
- (computing) A type of network cabling which satisfies plenum-ratings issued by the National Electrical Code. These cables are safer in case of a fire, producing less smoke and fumes.
From Latin plÄ“num, noun use of neuter of plÄ“nus (“full"). Influenced by Russian Ð¿Ð»ÐµÐ½ÑƒÐ¼ (plÃ©num, “plenary session"), from the same Latin source.
plenum - Computer Definition
An air-handling space such as those used for air conditioning and heating systems. Plenums commonly are between walls, under raised floor structures, and above drop (suspended) ceilings. While plenums are convenient places to run cables, they also are conducive to the spreading of fires within buildings, as they are primarily intended to support air flow. See also plenum cable.
In a building, the space between the real ceiling and the dropped ceiling, which is often used as an air duct for heating and air conditioning. It is also filled with electrical, telephone and network wires. See plenum cable.