plenum definition by Webster's New World
plenum definition by American Heritage Dictionary
noun pl. 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.
Origin: Latin plēnum (spatium), full (space), neuter of plēnus; see pelə-1 in Indo-European roots.
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.