Aloha is a word in the Hawaiian language that has numerous meanings both as a single word and when used in context with other words. The most common uses are as a greeting, farewell or a salutation. Aloha is also commonly used to mean love. It can also be used to express compassion, regret or sympathy.
On the Hawaiian Language Website, Aunty D states that
Aloha (and mahalo) are ineffable, indescribable, and undefinable with words alone; to be understood, they must be experienced. Deeper meaning and sacredness is hinted at by the root words of these words. Linguists differ in their opinions as to the exact meanings and origins, but this is what was told to me by my kupuna (elder): "On a spiritual level, aloha is an invocation of the Divine and mahalo is a Divine blessing. Both are acknowledgments of the Divinity that dwells within and without:
[Alo = presence, front, face] + [hā = breath]
'The presence of (Divine) Breath.'"
Aloha e (name) - Aloha to (person's name)
Aloha kākou - Aloha to all (including myself)
Aloha kāua - Aloha to you (singular) and me
Aloha nui loa - Very much love, fondest regards
Aloha ʻoe - Aloha to you (singular)
Aloha oukou - Aloha to all of you (plural)
Aloha kakahiaka - Good morning
Aloha awakea - Good noontime (10 a.m. to 2 p.m.)
Aloha ʻauinala - Good afternoon (2 p.m. to 6:00 p.m.)
Aloha ahiahi - Good evening (around sunset)
Aloha po - Good night