Definition of Duodecima

What is the meaning of the term Duodecima when it comes to football?

Duodecima in Spanish means twelfth (12th). When it comes to the game of football, it is Real Madrid's quest to win their twelfth Champions League trophy.

Real Madrid famously won their 'la decima' (10th) in 2013/14, followed by an 'undecima' in 2015/16.

Cristiano Ronaldo eying the Champions League trophy.  The Duodecima awaits.

When and if Los Blancos will win the 'duodecima' remains to be seen. If it does happen, will it be during the Cristiano Ronaldo era, or at some distant point in the future?

Maybe 2016/17 season is the one?