How do you pronounce Piazza Maggiore?

Say it PYAHT-tsah mahd-JOH-reh. In phonetic notation that is roughly /ˈpjattsa madˈdʒore/.

Piazza has two syllables, not three. The “pia” is one quick sound, like the start of “piano” said fast, and the stress falls on it. The double z is a “ts” sound, held a fraction longer than you would in English: PYAHT-tsah, not pee-AZ-ah.

Maggiore has three syllables and the stress goes in the middle, on “jo”. The double g is a “j” sound with a slight hold, which is why it can sound like “mad-jo” rather than “ma-jo”. Finish with a short, lightly tapped r and a clear “eh”. It is not “mag-ee-or” and not “major”.

If you are asking for directions, “Piazza Maggiore?” and a hopeful look works fine. Bolognesi will understand any reasonable attempt.