Baretti: A dictionary of the English and Italian languages
Fortézza, s. f.
1. firmness, courage, valour, intrepidity, fortitude; 2. force, power, strength;3. sourness; 4. a fortress, citadel; 5. force, power of resistance.
Florio: a worlde of wordes, or most copious, dictionarie in Italian and English
fortezza: a fort, a fortresse, a castle, a keepe, a skonce, a cittadell, a strength, a bulwarke, a hold, a block-house. Also fortitude, strength, force, power, valor.