This is the 6039th most frequent Spanish word.
acertijo
Riddle; a puzzling question or problem to solve.
Here, 'acertijo' is used to describe a challenging puzzle or riddle that requires mental effort to solve.
El acertijo era tan complicado que nadie pudo resolverlo.
The riddle was so complex that nobody could solve it.
In this case, 'acertijos' refers to riddles being used as a tool to engage others in critical thinking.
Me gusta plantear acertijos para hacer pensar a los demás.
I like posing riddles to make others think.
Here, 'acertijo' is applied to highlight the satisfaction derived from overcoming the challenge of a puzzle.