dog's letter

Calque of Latin littera canīna.

dog's letter

1. (rare) The letter R, which was trilled in Latin, imitating the sound of a snarling dog.
   • 1640, Samuel Ramsey, The English Language and English Grammar‎, New York and London: G.P. Putnam's Sons, translation of original by Ben Jonson, published 1892, page 168:

     R is the Dog's letter, and hurreth in the sound; the tongue striking the inner palate, with a trembling about the teeth.

   • 1858, Rosina Bulwer Lytton, The World and His Wife, Or, A Person of Consequence […] ‎, volume 2, London: Charles J. Skeet, page 19:

     And in this short query the dog's letter, the r, whirred through the air, like the ricket of a pheasant rising; […]