Definition of vacuum:
- A space entirely devoid of matter ( called also, by way of distinction, absolute vacuum); hence, in a more general sense, a space, as the interior of a closed vessel, which has been exhausted to a high or the highest degree by an air pump or other artificial means; as, water boils at a reduced temperature in a vacuum.
- The condition of rarefaction, or reduction of pressure below that of the atmosphere, in a vessel, as the condenser of a steam engine, which is nearly exhausted of air or steam, etc.; as, a vacuum of 26 inches of mercury, or 13 pounds per square inch.
senselessness, Hoover, mindlessness, void, vanity, desolation, pointlessness, nihility, blankness, emptiness, full, exhaustion, space, inanity, vacuum-clean, vacuity, barrenness, vacuum cleaner, rarefaction, nullity, nothingness, hollowness, vacancy.
- "Hertzian Wave Wireless Telegraphy", John Ambrose Fleming.
- "Amusement Only", Richard Marsh.
- "The Year When Stardust Fell", Raymond F. Jones.