Formidable (8 April 1975 – 1997) was an American-bred, British-trained Thoroughbred racehorse and sire. He showed his best form as a two-year-old when he won five consecutive races in little over a month, including the Mill Reef Stakes and the Middle Park Stakes. At the end of the year he was regarded as the best juvenile in Britain over a distance of six furlongs. In the following year he was campaigned over one mile and failed to win, although he was placed in the St James's Palace Stakes, the Sussex Stakes and the Waterford Crystal Mile. As a four-year-old he won three minor races and finished third in the Lockinge Stakes before being retired from racing. He later became a successful breeding stallion.