Synonyms for Good morning:

interj.

good day (interjection)
good morrow, greetings.
hello (interjection)
hi, Hey, hiya, good day.

n.

hello, hiya, all-right, good day, good evening, pleased to meet you, hi, Hey, good afternoon. communication (noun)
morning.
good day (noun)
good morrow, greetings.
good morning (noun)
morning.

Other synonyms:

hiya, good afternoon, good day, good evening, hi. Hey. all-right. how-do-you-do
hello.
Other relevant words:
hello, greetings, good morrow, good day.