nef vs nieve

nef

adj
  • Of a line bundle on a complete algebraic variety over a field: such that the degree of its restriction to every algebraic curve in the variety is non-negative. 

noun
  • An extravagant table ornament and container used in the Middle Ages and Renaissance, made in the shape of a ship. 

nieve

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