The superlative form of floaty; most inclined to float or having the greatest buoyancy.
From floaty + -est (superlative suffix). This superlative form extends the informal adjective floaty into its most extreme form, following standard English morphology patterns.
Using 'floatiest' is totally natural in English even though 'floaty' is very informal—our grammar rules work so well that native speakers instantly understand new superlatives, which is why children can invent words that sound completely right.
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