While it's best known as a greeting, "Aloha" also means "love" and "affection," making it a versatile word that encompasses both hello and goodbye.
However, there are other phrases you can use depending on the context:
* "A hui hou" (pronounced ah-hoo-ee-how) means "until we meet again."
* "Maika'i" (pronounced my-ky) means "good" or "well," and can be used as a more formal goodbye.
* "Ke aloha" (pronounced keh ah-loh-hah) is a more formal way of saying "goodbye" with love.
The best choice depends on the situation and your relationship with the person you're saying goodbye to.