nouns
an exaggerated expression (usually of praise)
"the critics lavished superlatives on it"
is a type of (narrower)
an expression of approval and commendation
"he always appreciated praise for his work"
the highest level or degree attainable; the highest stage of development
"his landscapes were deemed the acme of beauty"; "the artist's gifts are at their acme"; "at the height of her career"; "the peak of perfection"; "summer was at its peak"; "...catapulted Einstein to the pinnacle of fame"; "the summit of his ambition"; "so many highest superlatives achieved by man"; "at the top of his profession"
the superlative form of an adjective or adverb
"`fastest' is the superlative of the adjective `fast'"; "`least famous' is the superlative degree of the adjective `famous'"; "`most surely' is the superlative of the adverb `surely'"