colour in vs tint

colour in

verb
  • To colourise; to add colours to a black-and-white drawing, using coloured drawing equipment. 

tint

verb
  • To shade, to color. 

abbrev
  • it is not; it isn't; 'tisn't; it'sn't 

noun
  • A pale or faint tinge of any color; especially, a variation of a color obtained by adding white (contrast shade) 

  • A shaded effect in engraving, produced by the juxtaposition of many fine parallel lines. 

  • A vehicle window that has been darkened to conceal the occupant. 

  • A color considered with reference to other very similar colors. 

  • A slight coloring. 

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