In the book: "'I am dazed. I am dazzled with so much light. I am grateful to you, you so clever woman. Madame' - he said this very solemnly - 'if ever Abraham Van Helsing can do anything for you or yours, you must let me know.'"
Contextual definiton: in a serious way
Part of speech: adjective
Dictionary defintion: not cheerful or smiling; serious
Two synonyms: grave, sober
Sentence: Everyone at the funeral lowered their heads solemnly, as the marine was about to be buried.