from Wiktionary, Creative Commons Attribution/Share-Alike License.
superlativeform of necessary: most necessary.
Sorry, no etymologies found.
Verily this is one of the necessariest meditations in the World.
Since couerture is the most necessariest thing belonging vnto mans life, and that it was the first thing that euer man inuented, I thinke it not amisse first to beginne, before I enter into any other part of
(Meriar, elbow grease is one of the necessariest things in gettin 'a shine on a stove – don't let me catch you merely strokin' it again!)