least vs superlative

least and superlative both are nouns.

Word	Noun	Adjective	Verb	Adverb
least	Yes	Yes	No	Yes
superlative	Yes	Yes	No	No

least (noun)	superlative (noun)
something that is of no importance	an exaggerated expression (usually of praise)
	the superlative form of an adjective or adverb
	the highest level or degree attainable; the highest stage of development

least (adjective)	superlative (adjective)
the superlative of `little' that can be used with mass nouns and is usually preceded by `the'; a quantifier meaning smallest in amount or extent or degree	highest in quality

least (adverb)	superlative (adverb)
used to form the superlative, smallest in size or degree