A superlative adjective compares three or more nouns. This takes the comparison of nouns to the highest degree. The rules for making superlative adjectives are almost identical to the rules for making comparative adjectives. They are: One syllable words – add “est” to the word.
What is the difference between comparative and superlative adjectives?
Adjectives with two syllables can form the comparative either by adding -er or by preceeding the adjective with more. These adjectives form the superlative either by adding -est or by preceeding the adjective with most. In many cases, both forms are used, although one usage will be more common than the other.