grave vs solemn

grave

adj
  • Serious, in a negative sense; important, formidable. 

  • Low in pitch, tone etc. 

  • Characterised by a dignified sense of seriousness; not cheerful. 

noun
  • Death, destruction. 

  • Any place of interment; a tomb; a sepulcher. 

  • Deceased people; the dead. 

  • An excavation in the earth as a place of burial 

  • A written accent used in French, Italian, and other languages. è is an e with a grave accent (`). 

  • A count, prefect, or person holding office. 

solemn

adj
  • Deeply serious and sombre; grave. 

  • Characterized by or performed with appropriate or great ceremony or formality. 

  • Of or pertaining to religious ceremonies and rites; (generally) religious in nature; sacred. 

  • Inspiring serious feelings or thoughts; sombrely impressive. 

How often have the words grave and solemn occurred in a corpus of books? (source: Google Ngram Viewer )