(idiomatic) the time when help is most needed

Of necessity or need; necessarily.

(idiomatic) (of information) given to another only when necessary.

Something that one needs to know; a piece of necessary information.

(idiomatic) To need something immediately or urgently; to need something that is already late.

(programming) An evaluation strategy in which the arguments to a function are evaluated the first time they are used in that function.

plural of need-to-know

past participle of do the needful

(US, of a college admission policy) That requires the admitting institution to not consider an applicant's financial situation when deciding admission.

Alternative form of citation needed