This is the 938th most frequent Italian word.
massima
"Massima" in English means "maxim" (a concise statement of a general truth or principle).
Here, 'massima' is used to describe the highest value in a measurable context, specifically the temperature.
La massima del giorno è di 25 gradi Celsius.
The maximum of the day is 25 degrees Celsius.
In this context, 'massima' refers to a succinct and wise saying or aphorism.
Una massima famosa dice: 'Chi semina vento, raccoglie tempesta.'
A famous maxim says: 'He who sows wind harvests storm.'
Here, 'massima' is used as an adjective to indicate the highest or utmost degree of something, in this case, safety.