Salve, buongiorno are heard all day, buonasera in the evening. I have never ever heard buona mattina or buon pomerrgiggio. Buona giornata and serata are used in as a wish, as in Have a nice day rather than a greeting so are mostly used as you leave. Buon giorno is the equivalent of our good morning AND good afternoon
Yes, thanks Francesco. I was taught that so long ago, I forget, but since getting some contrary advice, have felt a bit anxious saying "Buona sera in the afternoon. Now Francesco has restored my confidence. Silly, because the opportunities for total humiliation when trying to speak another language are numerous.
Short answer (to an old question): yes, "greetings" would be a correct meaning for salve, when used as an interjection.
An alternative would be to say salute.
Interjection: hello (formal), hi (informal), hail!, greetings.
From Latin salvē, meaning hail!, welcome! farewell!
Typically used as a greeting that isn't associated with a particular time of day. As others have pointed out, saying "Salve, buongiorno!" would be a redundant double-greeting, or perhaps an emphatic hello.
Synonymous with ciao! From the Venetian expression s-ciao vostro - your servant/slave (meaning "I am at your service"). See other forum posts on the debate over which is more formal/informal, salve or ciao. From what I've read, regional differences aside, salve can be formal or informal, it's mostly down to the way you say it, whether respectfully or casually. Ciao is typically described as an informal greeting/farewell.
salvo (singular masculine), salva (singular feminine)
salvi (plural masculine), salve (plural feminine)
Adjective: safe, out of danger, saved, secure from, whole, intact, undamaged.
salvo (singular masculine), salvi (plural masculine)
Noun: in salvo = safe. in a safe place, ~ to safety (lead to safety, reach safety etc.).
Mettiti in salvo! = Save yourself! or Run for your life!
Preposition: except (for), but, barring, save (for).
Salvo imprevisti = All being well.
Conjunction: except that, save that, unless.
Verb (transitive): to save, rescue, retrieve, deliver, guard, safeguard, protect, defend.
Present tense - io salvo, tu salvi, lui/lei salva, noi salviamo, voi salvate, loro salvano.
From the Latin verb salvere, meaning "to be well". This could refer to physical health or spiritual. Deus vos salve ("God save you") became a common greeting in medieval times and can be found in works such as Shakespeare (and the computer game Kingdom Come: Deliverance, as anyone who has played it will know!).
Verb (reflexive): to save/protect/defend oneself/myself/himself/herself/ourselves/yourselves/themselves, escape, survive, hide. To be saved (spiritually).
Present tense - mi salvo, ti salvi, si salva, ci salviamo, vi salvate, si salvano.
An alternative way to express related sentiments is with salute.
Interjection: cheers!, bless you! your health!
salute (singular feminine), saluti (plural gender neutral)
Noun: health, wellbeing.
saluto (singular masculine), saluti (plural masculine)
Noun: hello, good morning, good night, goodbye, farewell, greetings, regards. A nod or wave of the hand, military salute. A short visit to a person.
salutare (gender neutral singular), salutari (gender neutral plural)
Adjective: healthy, wholesome, beneficial.
Verb (transitive): to welcome, to greet, to salute, to see off, to say goodbye, bid farewell, to give somebody's regards to somebody else, remember somebody to somebody else.
Present tense - io saluto, tu saluti, lui/lei saluta, noi salutiamo, voi salutate, loro salutano.
Verb (reflexive): to say hello, greet, say goodbye, farewell etc. to each other/one another.
Present tense - mi saluto, ti saluti, si saluta, ci salutiamo, vi salutate, si salutano.
Warning: this is based on my time in Bologna and surroundings - I'm a native English speaker. It seems people greet me with "salve" when I know them less well and they're clearly greeting me (eg, when joining a group on a bike ride in the hills). "Ciao" seems quite flexible - it can serve as a greeting with a closer friend, but also as a goodbye (on the phone, often in a string, eg "ciao, ciao, ciao, ciao, ciao" from a close friend, "ciao ciao" from someone less close).