Serious Serious synonyms severe serious and severe grave serious and grave dangerous serious and dangerous earnest serious and earnest solemn serious and solemn sober serious and sober grievous serious and grievous heavy serious and heavy important serious and important weighty serious and weighty Full list of synonyms (1961) Serious antonyms unimportant serious and unimportant trivial serious and trivial flippant serious and flippant light serious and light minor serious and minor frivolous serious and frivolous insignificant serious and insignificant funny serious and funny playful serious and playful unserious serious and unserious Full list of antonyms (148) Share this picture Share this image Share this picture Share this image