seriously UK /ˈsɪə.ɹi.əs.li/US /ˈsɪɹ.i.əs.li/adverb 5forms 2phrases 1 adverb5 •with real thought and care, not as a jokeHe was hoping that we would take him seriously.Jimmy jokingly called Bob a doofus. Bob took the insult seriously. •Gravely; deeply; very much.That was a seriously unpleasant thing to say. •(informal) In an extreme or major way; majorly.Unless you're seriously strapped (armed), you're about to be not okay too. •Used to call back to a previous point, in disbelief or for emphasis.You baked ten (10) cakes. Seriously, why did you do that? •Used to attempt to introduce a serious point in a less serious conversation.Now, seriously, why did you forget to feed the cat today? formsmore seriously · most seriously Phrases with seriously but seriously folksUsed to redirect attention to immediately preceding a failed attempt at humor.