Definitions

1. adjective

giving the impression that you are honest and willing to consider other people’s opinions, or showing that you are able to think carefully and make good decisions

“He gave a serious warning to the employees about the consequences of their actions.”

2. noun

a person who is considered to be a serious person, especially someone who is considered to be honest and responsible

“The serious man in the group tried to calm down the others.”

3. adverb

in a serious way, or with seriousness

“She spoke seriously about the importance of education.”