knitwear vs turtleneck

knitwear

noun
  • knitted garments 

turtleneck

noun
  • A high, close-fitting collar, turned back on itself and covering all or most of the neck, on a sweater or similar garment. 

  • A foreskin. 

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