inallseriousness
adverbUK /ɪn ɔːl ˈsɪəriəsnəs/
US /ɪn ɔl ˈsɪriəsnəs/
When you mean what you say and are not joking.
In all seriousness, we need to leave now or we will miss the bus.
OTHER MEANINGS
2. Used to show you are about to say something sincere after a joke.
In all seriousness, thank you for your help today.
3. Used to stress that a matter is important and should be treated carefully.
In all seriousness, this test decides your grade.
4. Used to signal a change from a light tone to a serious one.
We laughed a lot, but in all seriousness, safety comes first.