serious-minded Antonyms

absurd chowderheaded coo-coo coocoo crackbrained cray cray four sheets in the wind four sheets to the wind three sheets in the wind as silly as a goose silly as a goose one sandwich short of a picnic sheet in the wind beyond all reason as daft as a brush chuckle-headed cockle-brained cockle-headed away with the fairies akamai three sheets to the wind batty brainless clever crayfish cray crazy cuckoo daft elfish facetious hoity-toity light-minded stupid yeasty barmy goofy as a joke pulling one's leg