What does «albur» mean in Spanish?

In the game of monte, the first two cards drawn by the banker.
Chance, contingency.

Examples of use in Spanish: "tú no dejas nada al albur".

"merecía la pena correr el riesgo al albur".
A certain river fish. Read: albur (fish).
A play on words with a double meaning, especially of a sexual nature.