This is the 680th most frequent Catalan word.
doble
"Double."
In this sentence, the word "doble" is used as an adjective to describe something that has a duplicate or pair, implying the book has a cover consisting of two parts.
Aquest és un llibre de doble tapa.
This is a book with a double cover.
Here, "doble" modifies the noun "cafè" to mean a larger or strong portion, specifically referring to two standard servings of coffee.
Vaig demanar un cafè doble al bar.
I ordered a double coffee at the bar.
The term "doble" in this case signifies two possible or existing solutions, highlighting duality or multiplicity in the situation.