vacuum is the absense of pressure
vacuum - i
They mean that there are no air particles in space.
The different flashing lights on the Roomba vacuum mean refer to different status of the battery.
an electron tube containing a near-vacuum that allows the free passage of electric current.
get a vacuum and suck it up...
As an adjective, it means empty.
It means "vacuum cleaner".
Humans can, if that's what you mean.
If you mean specifically, what type of vacuum, the answer is manifold vacuum. Manifold vacuum is constant and doesn't, change with throttle valve opening, the way ported vacuum does.
To 'operate in a vacuum' means- A state of being sealed off from external or environmental influences; isolation.
'vacuum control module'
vacuum freazing, or you mean noble elements