Real Dictionary

vacuum
A vacuum is a space that contains no air or other gas.
If someone or something creates a vacuum, they leave a place or position which then needs to be filled by another person or thing.
verb: If you vacuum something, you clean it using a vacuum cleaner.

vacuum in American English
a space with nothing at all in it; completely empty space
of a vacuum
to clean with a vacuum cleaner

vacuum in American Englishfor 1, 2, 4, 6
adjective: of, pertaining to, employing, or producing a vacuum
intransitive verb: to use a vacuum cleaner
noun: a space entirely devoid of matter
transitive verb: to use a vacuum cleaner on; clean with a vacuum cleaner

vacuum in British English
noun: a region containing no matter; free space
verb: to clean (something) with a vacuum cleaner

vacuum in Hospitality
If you vacuum something, you clean it using a vacuum cleaner.