doner kebab vs kabaab

doner kebab

noun
  • A Turkish dish in which meat (typically seasoned lamb or mutton, but alternatively chicken or perhaps beef) is grilled on a revolving vertical spit; when cooked, the meat is sliced off and served with fresh vegetables in pita or rolled in a piece of unleavened flatbread. 

kabaab

noun
  • A dish of pieces of meat, fish, or vegetables roasted on a skewer or spit. 

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