Superlative form of select: most select.(adjective)
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Use "selectest" in a sentence
"Small wonder that Miss West remains sea-sick on an ocean like this, which has become a factory where the veering gales manufacture the selectest and most mountainous brands of cross-seas."
"We say, what an invention is the press and the journal, by which a hundred pale students, each a hive of distilled flowers of learning, of thought, — each a poet, — each an accomplished man whom the selectest influences have joined to breed and enrich, are made to unite their manifold streams for the information and delight of everybody who can read!"
"It would appear in the March issue of the journal; and these fools would then learn, to their eternal confusion, that they had among them one whose opinions were of weight in the selectest medical circles."