Very soon Italians will exchange Christmas wishes saying “buon Natale” to each other. Many wishes are similar to this one: “buon viaggio” (have a good trip!), “buon appetito” (enjoy your food!), buono studio (have a good day of study!)….
But why “Buon Natale” and “Buono studio”?
Why most of the times the finale “O” of buono is dropped?
First of all it’s important to highlight that “buono” is one of the few Italian adjectives that can be placed before the noun and not just in wishes. “un buon amico” is exactly the same thing as “un amico buono”; but again in the first version our good friend has lost the O of “buono”. Let’s see why! The adjective buono behaves exactly the same as the indefinite masculine articles (the words for “a” used in front of a masculine word): a friend in Italian is “un amico” but a study in Italian is “uno studio” therefore you say “buon amico” but “buono studio”.
Grammar
Before a consonant
Un Natale/buon Natale
Before s+consonant or z
Uno studio/buono studio
Before a vowel
Un amico/un buon amico
When “Buono” follows the noun it refers to it doesn’t drop the “O”: “un amico buono”, “un libro buono”….