disturbance vs intrusion

disturbance

noun
  • The act of disturbing, being disturbed. 

  • A noisy commotion that causes a hubbub or interruption. 

  • Something that disturbs. 

  • An interruption of that which is normal or regular. 

  • A serious mental imbalance or illness. 

intrusion

noun
  • The forcible inclusion or entry of an external group or individual; the act of intruding. 

  • The insertion of a phoneme into the pronunciation of a word despite its absence from the spelling. (e.g. intrusive r) 

  • A structure that lies within a historic district but is nonhistoric and irrelevant to the district. 

  • Magma forced into other rock formations; the rock formed when such magma solidifies. 

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