calve vs foal

calve

verb
  • to give birth to (a calf) 

  • to break off 

  • to shed (a large piece, e.g. an iceberg); to set loose (a mass of ice), e.g. a block of ice (coming off an iceberg) 

  • to assist in a cow's giving birth to a calf 

  • to shed a large piece, e.g. an iceberg or a smaller block of ice (coming off an iceberg) 

  • to give birth to a calf 

foal

verb
  • To give birth to (a foal); to bear offspring. 

noun
  • A young horse or other equine, especially just after birth or less than a year old. 

  • A young boy who assisted the headsman by pushing or pulling the tub. 

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