Feminine Noun Form

Some masculine given names become feminine by changing the ending and also adding a suffix

Examples:

Giuseppe —> Giuseppina
Nicola —> Nicoletta

In general, masculine common nouns ending in -a (but not in -ista, -cida), in -e, and also in -o, become feminine by adding the suffix -essa to the stem of the noun

Examples:

poeta (poet) —> poetessa (poet)
duca (duke) —> duchessa (duchess)
studente (male student) —> studentessa (female student)
principe (prince) —> principessa (princess)
avvocato (attorney) —> avvocatessa (female attorney)
soldato (soldier) —> soldatessa (female soldier)

Masculine common nouns ending in -sore become feminine by adding -trice to a modified stem

Examples:

difensore (defender) / difen-di-trice (female defender)
possessore (possessor) / posse-di-trice (female possessor)
uccisore (killer) / ucci-di-trice (female killer)

Exception:

professore (professor) / professoressa (female professor)

There are some specific nouns whose feminine form is obtained in a particular way.

Examples:

gallo (rooster) —> gallina (hen)
re (king) —> regina (queen)
dio (god) —> dea (goddess)
Doge (Doge)—> Dogaressa (Dogaressa)