Meaning of “necessity” - Learner’s Dictionary

necessity

noun uk us /nəˈsesəti/
NEED [ U ]

the need for something:

There's no financial necessity for her to work.
Sewing is something I do out of necessity, not for pleasure.
SOMETHING NEEDED [ C ]

something you need:

Most people seem to consider a car a necessity, not a luxury.

(Definition of “necessity” from the Cambridge Learner’s Dictionary © Cambridge University Press)