[Of doubtful origin.]
Perh. a use of prec. suggested by some resemblance in sound between this word and the It. name forchetta, or some dialectal variant of F. fourchette.
An elastic, horny substance growing in the middle of the sole of a horse’s hoof.
1610. Markham, Masterp., II. ci. 384. The Frush, which of some is called the Frogge of the foot, is the tenderest part of the hoofe towards the heele, and is fashioned like a forked arrow head, being onely that part of the foot which Farriers cut forth.
1727. Swift, Gulliver, IV. ix. They have excellent Medicines composed of Herbs, to cure accidental Bruises and Cuts in the Pastern or Frog of the Foot by sharp Stones, as well as other Maims and Hurts in the several Parts of the Body.
1840. Youatt, Horse, xviii. 376. In the space between the bars, and accurately filling it, is the frog. It is a triangular portion of horn, projecting from the sole, almost on a level with the crust, and covering and defending a soft and elastic substance called the sensible frog.
b. Comb.: frog-stay (see quot.).
1829. B. Clark, Hippodon. (ed. 2), 61. This cell or cleft of the frog is … prevented from rupturing inwards towards the quick by a stout considerable cone of horn passing directly from it into the sensitive frog…. This cone commences nearly opposite to the termination of the heels of the coffin-bone…. This part … being without even a name, I gave it the epithet frog-stay … from its closing the frog, and holding more firmly its halves together.
