ride a horse foaled by an acorn

• mount a horse foaled by an acorn
• ride a horse foaled of an acorn

ride a horse foaled by an acorn (third-person singular simple present rides a horse foaled by an acorn, present participle riding a horse foaled by an acorn, simple past rode a horse foaled by an acorn or (obsolete) rid a horse foaled by an acorn, past participle ridden a horse foaled by an acorn)

1. (obsolete, slang) To be hanged at the gallows.
   • 1670, Ray, John, “Proverbial Phraſes”, in A Compleat Collection of Engliſh Proverbs‎, fourth edition, published 1768, page 197:

     You'll ride on a horſe that was foal'd of an acron.
     That is; the gallows.

   • 1828, Bulwer-Lytton, Edward, chapter 82, in Pelham: or The Adventures of a Gentleman, page 385:

     "What ho, my kiddy!" cried Job, "don't be glimflashy; why you'd cry beef on a blater; the cove is a bob cull, and a pal of my own; and moreover, is as pretty a Tyburn blossom as ever was brought up to ride a horse foaled by an acorn."

   • 2003, Crummey, Michael, River Thieves, Houghton Mifflin Harcourt, →ISBN, page 272:

     Fourteen, sir. No age to be riding a horse foaled by an acorn, I can tell you.

   • 2008, Wilson, Barbara Ker, The Lost Years of Jane Austen, Ulysses Press, →ISBN, page 21:

     A sheep stealer, the mother told the child... and now the man twisted there, riding a horse foaled by an acorn, as the saying went, while the fat Welsh sheep in safety grazed the green pasture all around.

• [Francis] Grose [et al.] (1811), “Ride a horse foaled by an acorn”, in Lexicon Balatronicum. A Dictionary of Buckish Slang, University Wit, and Pickpocket Eloquence. […], London: Printed for C. Chappell, […], OCLC 23927885.