big toe vs digit

big toe

noun
  • The largest toe (usually) on each human foot (i.e. the toe closest to the other foot when the feet are flat on the ground, side by side, and the legs not crossed) or on a foot of certain other animals. 

digit

noun
  • A narrow extremity of the human hand or foot: a finger, thumb, or toe. 

  • The whole numbers from 0 to 9 and the Arabic numerals representing them, which are combined to represent base-ten numbers. 

  • A distinct symbol representing one of an arithmetic progression of numbers between 0 and the radix. 

  • ¹⁄₁₂ the apparent diameter of the sun or moon, (chiefly) as a measure of the totality of an eclipse. 

  • A unit of length notionally based upon the width of an adult human finger, standardized differently in various places and times, (especially) the English digit of ¹⁄₁₆ foot, now equivalent to about 1.9 cm. 

  • Similar or similar-looking structures in other animals. 

verb
  • To point at or point out with the finger. 

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