|Origin:||necessarius, from necesse 'necessary', from ne- 'not' + cedere 'to give up'|
ne‧ces‧sa‧ry1 S1 W1
something that is necessary is what you need to have or need to do [↪ essential]:
The booklet provides all the necessary information about the college.
No further changes were considered necessary.
The police are advising motorists to travel only if their journey is absolutely necessary.
it is necessary (for somebody) to do something
It's not necessary to wear a tie.
The doctor says it may be necessary for me to have an operation.
make it necessary (for somebody) to do something
Falling profits made it necessary to restructure the business.
necessary for (doing) something
A good diet is necessary for maintaining a healthy body.
I'll stay up all night, if necessary, to get it finished.
a connection, result etc that must exist and cannot be avoided:
The closure of the factory was a necessary consequence of increased competition from abroad.
something bad or unpleasant that you have to accept in order to achieve what you want:
Mr Hurst regarded work as a necessary evil.