martingale
/ˈmɑːtɪŋɡeɪl
/noun
1A strap or set of straps running from the noseband or reins to the girth of a horse, used to prevent the horse from raising its head too high.Other safety items are available that can be attached to reins, stirrups and martingales, as well as fluorescent saddlecloths and exercise rugs....
- To learn the two track maneuver, use a martingale or a snaffle bit with draw reins to encourage the horse to flex through the poll and keep his head still.
- A martingale on the horse broke but it was not clear what role, if any, that played in the accident and injury.
2 [mass noun] A gambling system of continually doubling the stakes in the hope of an eventual win that must yield a net profit.Caught in such a trend, living a life that matches the pace and the cost of change becomes a gamble on martingale terms - the stakes are doubled after every loss....
- The existence of equivalent martingale measures was proved by Harrison and Kreps.
- The alternative is to define probability in terms of games rather than measure (this was started by von Mises and greatly advanced by Ville, who in 1939 replaced von Mises's awkward gambling strategies with what he called martingales).
Origin
Late 16th century: from French, from Spanish almártaga, from Arabic al-marta‘a 'the fastening', influenced by martingale, from Occitan martegal 'inhabitant of Martigues (in Provence').