Citations:horse dick

Noun: "(vulgar, slang) a very large penis"

 * 2009 — Cairo, The Cat Trap, Strebor Books (2009), ISBN 9781593092283, page 182:
 * My pussy was hot, tight, and creamy from the big horse dick he was servin' me.
 * 2010 — Garland, "The Web Cam Bois", in Video Boys (ed. Mickey Erlach), STARbooks Press (2010), ISBN 9781934187739, page 188:
 * "Suck my big fat horse dick," he commanded.
 * 2012 — Bob Vickery, "Escorts", in Middle Men: Gay Erotic Threesomes (ed. Shane Allison), Cleis Press (2012), ISBN 9781573447935, pages 74-75:
 * Spike obligingly plows my mouth with that horse dick,