Definition of "martingale" [mar•tin•gale]

• The strap of a horse's harness that connects the girth to the noseband and is designed to prevent the horse from throwing back its head. (noun)
• Nautical Any of several parts of standing rigging strengthening the bowsprit and jib boom against the force of the head stays. (noun)
• Games A method of gambling in which one doubles the stakes after each loss. (noun)
• A loose half belt or strap placed on the back of a garment, such as a coat or jacket. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Under all bowsprits on schooners, to guy the headstays, thrusts downward a short spar, at right angles to the bowsprit; it is called the martingale or dolphin-striker."
• "Your example of 'martingale' is a good one - I vaguely know that it's a piece of horse harness, but I don't know exactly where it goes, what it does or why it matters."
• "Discovering that his martingale had more slack in it than usual, he proceeded to give an exhibition of rearing and hind-leg walking."