noun
Etymology: double (I) + cross
1. : an act of treachery : betrayal
politics is too full of stories of double crosses and sellouts — D.D.McKean
master of the art of the double cross — D.G.Haring
a. : an act of winning or trying to win a fight or match after agreeing to lose it
b. : an act of betraying a person with whom one is associated in an enterprise
2. : a cross between first-generation hybrids of four separate inbred lines (as in the production of hybrid seed corn)