classical vs heavy metal

classical

noun
  • One that is classical in some way; for example, a classical economist. 

adj
  • Of or pertaining to established principles in a discipline. 

  • Of or relating to the first class or rank, especially in literature or art. 

  • Describing art music (rather than pop, jazz, blues, etc), especially when played using instruments of the orchestra. 

  • Describing Western music and musicians of the late 18th and early 19th centuries. 

  • Of or pertaining to the ancient Greeks and Romans, especially to Greek or Roman authors of the highest rank, or of the period when their best literature was produced; of or pertaining to places inhabited by the ancient Greeks and Romans, or rendered famous by their deeds. 

  • Pertaining to models of physical laws that do not take quantum or relativistic effects into account; Newtonian or Maxwellian. 

  • Conforming to the best authority in literature and art; chaste; pure; refined 

  • Knowledgeable or skilled in the classics; versed in the classics. 

heavy metal

noun
  • A genre descended from rock music, characterized by massive sound, highly amplified distortion, and overall loudness, often with extended guitar solos, and lyrics that involve aggressive or fantastic imagery. 

  • Any metal that has a specific gravity greater than about 5, especially one, such as lead, that is poisonous and may be a hazard in the environment. (There are many different definitions of what counts as a heavy metal; see Heavy metals for a discussion.) 

  • Great influence or power. 

  • guns or shot of large size. 

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