The Collaborative International Dictionary of English v.0.48:

Necessitude \Ne*ces"si*tude\, n. [L. necessitudo, fr. necesse.
   See Necessray.]
   1. Necessitousness; want. --Sir M. Hale.
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   2. Necessary connection or relation.
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            Between kings and their people, parents and their
            children, there is so great a necessitude,
            propriety, and intercourse of nature. --Jer. Taylor.
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