Definition of necessity
1 : the quality or state of being necessary He questioned the necessity for the change.
2a : pressure of circumstance The plane was compelled by necessity to change its course.
b : physical or moral compulsion did it, not because he wanted to, but by necessity
c : impossibility of a contrary order or condition submitting to the necessity imposed by the physical laws of the universe
3 : the quality or state of being in need especially : poverty had come to help them in their necessity
4a : something that is necessary : requirement Many families could not afford the bare necessities of life.
b : an urgent need or desire When his father collapsed, an ambulance became a necessity.
: in such a way that it cannot be otherwise also : as a necessary consequence further changes will occur of necessity
Love words? Need even more definitions?Merriam-Webster unabridged
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