The condition of rarefaction, or reduction of pressure below that of the atmosphere, in a vessel, such as the condenser of a steam engine, which is nearly exhausted of air or steam, etc. Example: a vacuum of 26 inches of mercury, or 13 pounds per square inch
A spacetime having tensors of zero magnitude
All clues having "VACUA"
for an answer:
You can find a list of possible crossword clues for VACUA below.