no longer topical vs obsolete

no longer topical

obsolete

adj
  • No longer in use; gone into disuse; disused or neglected (often in favour of something newer). 

  • Imperfectly developed; not very distinct. 

verb
  • To cause to become obsolete. 

How often have the words no longer topical and obsolete occurred in a corpus of books? (source: Google Ngram Viewer )