How do you form the superlative of Spanish adjectives?

To form the superlative in Spanish, you use the adverbs más (more) and menos (less). For example, the word for "big" in Spanish is grande. To say "biggest", you simply tack más on before grande, to make más grande. If you want to say "the biggest", you must add el or la to the phrase to form el más grande or la más grande. Similarly, you can use menos to signal that something is the smallest, which would be el menos grande.