козырь

Etymology 1
Attested first from the year 1731, borrowed from, also , variants of , , a dialectal variant – already attested in the 16th century in the sense “trump” – of , , from , also ,.

Compare as another cardgame term that has passed into Russian from Polish:.

Noun

 * 1) trump
 * 2)  main argument, used in the right time to gain advantage
 * 3)  unrevealed or hidden advantage

Etymology 2
(att. 1641),. Origin, but suggested to be connected to коза.

Noun

 * 1)  high standing collar
 * 2)  or  canopy over a horse-drawn cart, sleigh
 * 3)  or  peak, visor