altus, _high_, altior, _higher_, altissimus, _highest_.
trīstis, _sad_, trīstior, _sadder_, trīstissimus, _saddest_.
(2.) SUPERLATIVE #-rimus#.
344. Adjectives with the nominative in #-er# have the nominative of the
superlative like the nominative of the positive with #-rimus# added
(350): as,