headlamp vs reflector

headlamp

noun
  • An individual headlight, particularly of a motor vehicle. 

  • A flashlight worn on the head. 

reflector

noun
  • A small, often red, reflecting disk on the rear of a vehicle or bicycle that reflects the headlights of other vehicles. 

  • A reflecting telescope. 

  • One who reflects on something; one who thinks or considers at length. 

  • Something which reflects heat, light or sound, especially something having a reflecting surface. 

  • A safety reflector. 

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