[ple.num] n, pl -nums or -na [NL, fr. L, neut. of plenus] (1678) 1 a: a space or all space every part of which is full of matter b (1): a condition in which the pressure of the air in an enclosed space is greater than that of the outside atmosphere (2): an enclosed space in which such a condition exists
2: a general assembly of all members esp. of a legislative body
3: the quality or state of being full