1in a solemn or considered manner:the doctor looked seriously at him
2with earnest intent; not lightly or superficially:I seriously considered cancelling my subscription
really or sincerely:do you seriously believe that I would jeopardize my career by such acts?
[sentence adverb] used to add sincerity to a statement, especially after a facetious exchange of remarks:seriously though, short cuts rarely work
3to a degree that is significant or worrying:the amount of fat you eat can seriously affect your health [as submodifier]:three men are seriously ill in hospital
4 [as submodifier] informal very; extremely:he was seriously rich
take someone/thing seriously
regard someone or something as important and worthy of attention:such threats have to be taken seriouslyhe takes himself too seriously